JP6604535B2 - Frequency multiplex readout device - Google Patents

Description

  The present invention relates to frequency multiplex readout devices, and more particularly to frequency multiplex readout devices for large scale superconducting detector arrays.

  The superconducting transition edge sensor (TES), which is a thermal detector that boasts the ultimate low-noise characteristics using the temperature dependence of the abrupt resistance associated with the transition between superconducting and normal conducting, is (i ) Energy resolution more than an order of magnitude better than semiconductor detectors in X-ray and γ-ray analysis (energy dispersive spectroscopy), (ii) Nearly 100% quantum efficiency and response time of less than 200ns for single photon detection in the near infrared region, (Iii) In the millimeter-wave and submillimeter-wave regions, we have demonstrated low noise and high-speed response, which are far superior to cooling semiconductor bolometers. Also, in the spring of 2014, news that there was a possibility of discovering gravitational waves generated during the creation of the universe as a result of polarization observation by cosmic microwave background radiation with TES was popular in the world.

  However, TES has a smaller detection area (light receiving area) than a room temperature detector and is inferior in imaging function. However, TES has a characteristic that the temperature increase ΔT (= E / Cv) is larger as the TES having a smaller heat capacity Cv with respect to the photon incidence of energy E. Thus, by increasing the detection area by arranging a large number of TES having a low Cv, that is, a small light receiving area, it becomes possible for the first time to achieve both low noise / high-speed response and increase in the detection area, and also improve the spatial resolution.

On the other hand, the increase in the number of pixels of TES has led to an increase in the number of signal extraction wires from a TES operating in a cryogenic environment to a signal processing system operating in a room temperature environment, and accordingly, via a wiring from room temperature to cryogenic temperature. Increases heat inflow. Usually, a plurality of cryogenic stage temperatures at which the sample is arranged are provided. In the case of the TES cooling system, the TES is often placed on the 0.1K stage, and the subsequent cryogenic reading device is placed on the 4K stage. The cooling efficiency of the cryogenic refrigerator that dominates the volume, power consumption and price of the superconducting detector system is as low as 10 ⁻⁷ %@0.1K and 10 ⁻² % @ 4K. For example, a refrigerator having an exhaust heat capacity of 10 μW at a typical operating temperature of 0.1 K of X-ray TES has a power consumption of 9 kW with a three-phase AC 200 V power source, a volume of about 2000 mm in length, 600 mm in width, about 1000 mm in height, The price is 30 million yen, and it becomes a barrier to popularization and commercialization as an advanced measurement analyzer.

  Therefore, signal multiplexing technology that reduces heat inflow by multiplexing signals from a large number of TESs and reading out signals with a small number of wires is (i) high performance of TES, (ii) increase of light receiving area and expansion of imaging function, (Iii) In order to satisfy the seemingly contradictory requirements of downsizing, low power consumption, and low price of a superconducting detector system, it is extremely important along with uniformizing the characteristics of a multi-pixel TES. The signal multiplexing method includes a time multiplexing method and a frequency multiplexing method. Here, a frequency multiplexing method in which the signal-to-noise ratio does not decrease with the number of multiplexing is taken up.

  In recent years, a frequency multiplex reading apparatus using microwave band resonance of several GHz has been proposed (see, for example, Non-Patent Document 1). FIG. 8 shows a configuration diagram of an example of a main part of the frequency multiplex reading apparatus proposed above. In FIG. 8, a multiplexing chip 50, which is a main part of the frequency multiplex reading device, has a configuration in which a detection chip 51 and a reading chip 52 are connected by M coils 541 to 54M (only three are shown in FIG. 8). Yes, a frequency division multiplexed signal in the microwave band from the microwave signal source 64 is input. The microwave signal source 64 generates a frequency division multiplexed signal composed of M frequency signals. Note that the frequency multiplex reading device has a modulator that up-converts a baseband signal into a microwave band signal on the input side of the multiplexing chip 50, and downconverts the microwave band signal into a baseband signal on the output side. A demodulator and an analyzer for analyzing the demodulated signal;

  In FIG. 8, the detection chip 51 is composed of M TESs 531 to 533 (only three of which are shown in FIG. 8), and each is supplied with a DC bias current from a DC signal source 65 via a resistor R. Yes. The TES 531 to 53M detect energy such as photons or electromagnetic wave amplitude from an external detection target. The reading chip 52 includes input coils 551 to 55M, coils 561 to 56M, Josephson junctions 571 to 57M, lines 581 to 58M, capacitors 591 to 59M, and lines 610 and 611 to 61M.

  Here, the j-th (j = 1 to M: the same applies hereinafter) coil 56j in the readout chip 52 is a superconducting quantum interference element (SQUID) that is a superconducting closed circuit together with the Josephson junction 57j. Further, it is inductively coupled with the input coil 55j. The output terminal of the SQUID is connected to a connection point between the lines 61 (j-1) and 61j through a line 58j and a capacitor 59j in series. The line 61M is connected to the outside through an amplifier (hereinafter referred to as a HEMT amplifier) 62 and a line 63 which are configured by a high electron mobility transistor (HEMT). The multiplexing chip 50 and the HEMT amplifier 62 are accommodated in the cryogenic cooling device 60.

  The input coil 55j, the SQUID composed of the coil 56j and the Josephson junction 57j, the line 58j and the capacitor 59j constitute a jth resonance circuit. The resonance frequency of the j-th resonance circuit is set to be the same as the j-th frequency signal among the M frequency signals constituting the frequency division multiplexed signal in the microwave band from the microwave signal generation source 64. . As a result, the multiplexing chip 50 changes the resonance frequency of the j-th resonance circuit within a slight frequency width in accordance with the detection signal of the j-th TES 53 j, whereby the microwave band from the microwave signal generation source 64 is changed. The phase and amplitude of the j-th frequency signal in the frequency division multiplexed signal are changed and output.

  FIG. 9 (a) shows the frequency vs. transmittance characteristics of the frequency multiplexed signal output from the multiplexing chip 50, and FIG. 9 (b) shows the frequency vs. transmission obtained by enlarging the part indicated by a circle in FIG. The rate characteristic is shown. FIG. 9A shows an example in which M = 16, and the frequency signal of the second (j = 2) dip in the frequency division multiplexed signal (so-called frequency comb signal) having dip at 16 frequencies is shown in FIG. As shown in (b), the phase and amplitude change according to the signal from the second TES. As the signal from the second TES becomes weaker, the phase and amplitude of the frequency signal of the second dip change as indicated by I, II, and III in FIG. 9B. The phase and amplitude of the frequency signal of the second dip are demodulated by a signal processor at the subsequent stage, and based on this, the detection result is analyzed using a computer.

Here, it is known that the fundamental number of pixels M _p of a frequency division multiplexed signal that can be multiplexed per pair of readout signal lines (round trip) is given by the following equation.
M _p = B / (κD) (1)
However, in the above equation, B is the band of the readout signal line (determined by the readout circuit), D is the band of one pixel signal (determined by the detection target), and κ is the ratio of the adjacent resonance frequency interval to D (note that between pixels) According to Non-Patent Document 1, the condition that the crosstalk satisfies less than −30 dB is κ> 10).

In the frequency multiplex readout device of the first generation superconducting detector, which is well known in the art, when measuring a measurement target having a readout signal band B of about 5 MHz and a 1-pixel signal band of 100 kHz, the fundamental number of pixels M can be calculated from equation (1). _p is only about 5. On the other hand, the second-generation superconducting detector frequency multiplex readout apparatus using microwaves for readout explained in conjunction with FIGS. 9 and 10 is arranged at the subsequent stage of the multiplexing chip 50 that performs multiplexing in a cryogenic environment. Since the band B of the HEMT amplifier 62 is, for example, 4 GHz ≦ B ≦ 10 GHz, the fundamental number of pixels M _p is as much as 2 to 3 digits of that of the above-mentioned first generation frequency multiplex readout device from the equation (1). The number of pixels can be increased.

  In addition, since the resonator length generally decreases in inverse proportion to the resonance frequency, when a resonator that operates at a resonance frequency of several GHz is provided as in the second-generation frequency multiplex readout device, the size of the resonator is reduced. Since the resonance frequency can be reduced by about three orders of magnitude compared with the first generation frequency multiplex readout device having a frequency of several MHz, the possibility of large-scale integration by superconducting thin film on a chip based on integrated circuit technology, This is advantageous in terms of controllability and uniformity of the characteristics of the manufactured resonator. Furthermore, according to the second generation frequency multiplex readout device, the power loss (and hence the heat generation at the very low temperature) is reduced by changing the operation mode of the element used for reading out the TES signal in the multiplexing chip operating in the microwave band. The power consumption can be reduced to several picowatts per pixel, which is smaller than the power consumption, and the signal from the DC drive TES can be frequency-division multiplexed.

J.A.B.Mates, et al .: “Demonstration of a multiplexer of dissipationless superconducting quantum interference devices”, Appl. Phys. Lett., 92 (2008), 023514 1-3

However, according to the second generation frequency multiplex reading device, the band of a signal processor (not shown in FIG. 8), which is disposed in the subsequent stage of the multiplexing chip 50 and operates in a room temperature environment, is, for example, Since the 14-bit commercial product has only about 0.25 GHz, the band of the read signal of the frequency multiplex reading device is not limited to the band B of the HEMT amplifier 62 (4 GHz ≦ B ≦ 10 GHz as described above). Is limited to about 0.25 GHz, which is the bandwidth of the A / D conversion unit constituting the signal processor. Therefore, when the band D of one pixel signal in the equation (1) is 100 kHz and the ratio κ between adjacent resonance frequency intervals and D is “10”, the theoretical pixel number M _p is about 250 from the equation (1). It becomes. From this, for a detection target that requires a dynamic range corresponding to a 14-bit A / D conversion unit, the theoretical number of pixels M _p can be obtained only at most “250”. The number of pixels can be increased by a factor of about 50 times, while the theoretical number of pixels of the second generation frequency multiplex readout device can be increased by only 1/16 to 1/40.

  For this reason, for example, in a development project of several thousand pixel superconducting detector cameras in Europe and the United States, as shown in FIG. 10, the multiplexing chip in the cryogenic environment and the signal processing system in the room temperature environment are arranged in parallel in N systems. It is unavoidable to multiplex the pixel signals of K pixels for each individual system and to read out pixel signals N times as many as K pixels in all systems. That is, the frequency multiplexing readout apparatus shown in FIG. 10 includes arbitrary waveform generators 711 to 71N, and is the i-th (i is 1 to N; the same applies hereinafter) arbitrary waveform among N arbitrary waveform generators 711 to 71N. On the output side of the generator 71i, an upconverter comprising a local oscillator 73i and a frequency converter 72i, a level attenuator 74i, a multiplexing chip 50i, a circulator 75i, a HEMT amplifier 62i, an amplifier 76i, a local oscillator 73i and a frequency converter 77i. The down-converter and the signal processor 78i are connected in cascade, and are connected in parallel in N systems in total.

  Each of the arbitrary waveform generators 711 to 71N generates a frequency division multiplexed signal composed of M frequency signals in the baseband of an arbitrary waveform having the same amplitude. This frequency division multiplexed signal is a so-called frequency comb signal having a line spectrum at M frequencies as shown in FIG. Further, the arbitrary waveform generators 711 to 71N as a whole generate N frequency comb signals having different frequencies.

  The local oscillators 731 to 73N oscillate and output the same local oscillation frequency fc. Each of the N up-converters up-converts the input baseband frequency division multiplexed signal into a microwave band of several GHz, for example, and supplies it to the multiplexing chips 501 to 50N having the configuration shown in FIG. To do. The level attenuators 741 to 74N, the multiplexing chips 501 to 50N, the circulators 751 to 75N, and the HEMT amplifiers 621 to 62N are housed in the same cryogenic cooling device (cryostat) 60 and operate in a cryogenic environment. Otherwise, it operates at room temperature. The signal processors 781 to 78N perform demodulation operations on the down-converted baseband frequency division multiplexed signals independently of each other by fast Fourier transform (FFT). The computer (PC) 79 analyzes the digital signals from the signal processors 781 to 78N and separately detects the amplitude and phase of each of N × M frequency signals constituting the frequency division multiplexed signal.

  However, the frequency multiplex readout apparatus having the N system configuration is operated with a cryogenic cooling device 60 and an external room temperature environment between the N system up-converter and the N system down-converter. The number of lines) is 2N in total. For this reason, the heat inflow power through the signal line to the detector stage (≈0.1K) for N = 40 is very fine (outer diameter 0.86 mm) and the cupro nickel (CuNi) coaxial with poor heat conduction to the signal line. Even if a wire is used, it reaches several μW. Furthermore, the heat generation (≈20 mW / piece) of the semiconductor amplifier group placed on the 4K stage of the cryogenic cooling device 60 also becomes N times. These are small and low power consumption that is compatible with general-purpose superconductivity analyzers, even if they are allowed in basic science projects in Europe and the United States that assume large-scale, high-power refrigerators, such as astronomy / cosmic background radiation and observation of dark matter.・ The exhaust heat capacity of an inexpensive refrigerator is overloaded.

  The present invention has been made in view of the above points, and has a configuration in which the number of signal lines between room temperature and cryogenic temperature is only two, and the entire band of an amplifier operating in a cryogenic environment can be used. Therefore, an object of the present invention is to provide a frequency multiplex readout apparatus that can dramatically increase the number of pixels per signal line.

  In order to achieve the above object, the frequency multiplexing read apparatus of the present invention includes a read chip 52 including M superconducting resonance circuits having different resonance frequencies (where M is a natural number of 2 or more), There are N multiplexing chips (where N is 2 or more) including detection chips 51 including M superconducting detectors that change each resonance frequency of the superconducting resonance circuit independently of each other according to a detection signal. (Natural number) are connected in cascade with different resonance frequencies, and in a high frequency band composed of M × N frequency signals having the same frequency as the resonance frequency of M × N superconducting resonance circuits in N reading chips. A second frequency division of a high frequency band composed of M × N frequency signals which are supplied with a first frequency division multiplexed signal and whose amplitude and phase are controlled in accordance with detection signals of M × N superconducting detectors. Cascade connection that outputs multiple signals A multiplexing amplifier 171 to 17N, a wideband amplifier 19 that amplifies and outputs the second frequency division multiplexed signal output from the cascade connection multiplexing chip, and an arbitrary waveform in which M frequency signals are frequency division multiplexed. N baseband signals, which are signals in the first band, are generated by making the frequencies of the frequency signals different from each other, and the N baseband signals are generated in a high frequency band and N different bands. Up-converting to a high-frequency signal, frequency-division-multiplexing the N high-frequency signals after up-conversion, and generating a frequency-division multiplex signal with the overall bandwidth set to a second band that is equal to or less than the bandwidth of the wide-band amplifier Frequency division multiplex signal generation means 111 to 11N, 121 to 12N, 131 to 13N for supplying a cascade connection multiplexing chip as a first frequency division multiplex signal, and a wideband amplifier Signal distribution means 211 to 21m for distributing the second frequency division multiplexed signal output from the N frequency distribution, and the N second frequency division multiplexed signals distributed by the signal distribution means to each of M frequencies having different frequencies. Down-converting means 221 to 22N, 241 to 24N, 121 to 121N for down-converting into N baseband signals in the first band of signals, and amplitudes of N baseband signals output from the down-converting means and Analyzing means 251 to 25N and 26 for analyzing the phase. Here, the M × N superconducting detectors constituting the cascade multiplexing chip constitute a large-scale superconducting detector array, and the cascade multiplexing chip and the broadband amplifier are in a cryogenic environment. In operation, the cascaded multiplexing chips are supplied with the first frequency division multiplexed signal from the frequency division multiplexed signal generating means operating in a room temperature environment via one first signal line, The second frequency division multiplexed signal is supplied via a single second signal line to the signal distribution means operating in a room temperature environment through a broadband amplifier.

  In order to achieve the above object, according to the frequency division multiplexing apparatus of the present invention, the first and second frequency division multiplexed signals in the high frequency band have the same resonance frequency as the M × N superconducting resonance circuits. It is a frequency division multiplexed signal in a microwave band composed of frequency comb signals in which frequency line spectra are arranged in a comb shape.

  In order to achieve the above object, the frequency division multiplexing read-out device according to the present invention is configured such that the cascade-multiplexed chip includes one M number of microwave dynamic inductance detectors that serve both as the detection chip and the read chip. The multiplexing chip has a configuration in which N pieces are cascade-connected.

  In order to achieve the above object, according to the frequency multiplex readout apparatus of the present invention, the M superconductor detectors constituting the detection chip 51 are M superconducting transition edge detectors. Features.

  In order to achieve the above object, according to the frequency multiplex readout apparatus of the present invention, the M superconductor detectors constituting the detection chip are formed of metal magnets composed of M differential coils of superconductors. It is a calorimeter.

  In order to achieve the above object, the frequency multiplex readout apparatus according to the present invention includes a superconducting loop in which M superconductor detectors constituting a detection chip include a superconductor detection coil. The M SQUID magnetometers are individually magnetically coupled to the M superconducting resonance circuits having Josephson junctions that constitute the structure.

  In order to achieve the above object, in the frequency multiplex readout apparatus according to the present invention, the analyzing means converts the corresponding baseband signal among the N baseband signals output from the downconverting means to A / D. N signal processors whose bandwidth is equal to or less than the bandwidth of the input baseband signal to be converted, and a computer that performs analysis based on the digital signals output from the N signal processors It is characterized by.

  According to the present invention, the number of signal lines between the room temperature environment and the cryogenic cooling device can be greatly reduced, and heat inflow through the signal line to the cryogenic cooling device can be significantly suppressed. In addition, according to the present invention, since the entire bandwidth of a wide-band amplifier that operates in a cryogenic environment can be used, a pixel signal (frequency division multiplexed signal) with an extremely high number of pixels can be read compared to the conventional art.

It is a block diagram of one Embodiment of the frequency multiplex reading apparatus which concerns on this invention. (a) is the output spectrum of each arbitrary waveform generator in FIG. 1, (b) is the input spectrum of L1 in FIG. 1, and (c) is one of the cascaded multiplexing chips in FIG. It is a figure which shows the frequency dependence of the permeation | transmission rate. It is a figure which shows an example of the cascade connection method of the multiplexing chip | tip in this invention. It is a block diagram of the principal part of 2nd Embodiment of the frequency division multiplexing apparatus which concerns on this invention. It is a block diagram of the detection chip | tip which is the principal part of the multiplexing chip | tip in 3rd Embodiment of the frequency multiplex reading apparatus based on this invention. It is a block diagram of the detection chip | tip which is the principal part of the multiplexing chip | tip in 4th Embodiment of the frequency multiplex reading apparatus based on this invention. It is a figure which shows the other example of the cascade connection method of the multiplexing chip | tip in this invention. It is a block diagram of an example of the multiplexing chip | tip of the principal part of the conventional frequency multiplexing apparatus. FIG. 9 is an example of a frequency vs. transmittance characteristic diagram of a frequency multiplexed signal output from the multiplexing chip of FIG. 8 and a frequency vs. transmittance characteristic diagram in which a part thereof is enlarged. It is a block diagram of an example of the conventional frequency multiplex reading apparatus.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration diagram of an embodiment of a frequency multiplex readout apparatus according to the present invention. As shown in the figure, the frequency multiplexing readout apparatus 10 of the present embodiment includes N arbitrary waveform generators 111 to 11N, N local oscillators 121 to 12N, and N frequency converters (single sidebands). Mixer) 131 to 13N, N low-pass filters (LPF) 141 to 14N, 2-input 1-output multiplexers 151 to 15m, level attenuator 16, and N multiplexed chips connected in cascade 171 to 17N, a circulator 18, a single HEMT amplifier 19, a single low noise amplifier 20, m 1-input 2-output duplexers 211 to 21m, and N band-pass filters (BPF) ) 221 to 22N, N amplifiers 231 to 23N, N frequency converters (mixers) 241 to 24N, N signal processors 251 to 25N, and a computer (PC) 26, Cryogenic cooling device The multiplexing chips 171 to 17N and the HEMT amplifier 19 in the Cry have a single system configuration.

  Each of the arbitrary waveform generators 111 to 11N generates a baseband frequency division multiplexed signal having an arbitrary waveform in which M frequency signals having different frequencies are multiplexed. Here, each of the arbitrary waveform generators 111 to 11N generates a frequency comb (comb) signal in which M line spectra (frequency signals) are arranged in a comb shape as shown in FIG. 2A as an arbitrary waveform. To do. The signal bandwidth A of the frequency comb signal output from each of the arbitrary waveform generators 111 to 11N is the same, and is equal to or smaller than the bandwidth of each of the signal processors 251 to 25N described later and as close as possible. Arbitrary waveform generators 111 to 11N are set such that the frequencies of M peaks in the frequency comb signals generated are different from each other. Therefore, the arbitrary waveform generators 111 to 11N generate frequency comb signals composed of different M × N frequency signals in the baseband having the same amplitude as a whole. In this specification, for the sake of convenience, the frequency comb signal generated by the arbitrary waveform generator 111 is referred to as a first frequency comb signal, and similarly, the arbitrary waveform generators 112, 113,. The frequency comb signals generated by 11N are referred to as second, third,..., Nth frequency comb signals.

The local oscillators 121 to 12N oscillate and output different local oscillation frequencies f _{c1 to} f _cN . The frequency converters 131 to 13N constitute a corresponding local oscillator and up-converter among the local oscillators 121 to 12N. That is, the i-th (i = 1 to N; hereinafter the same) frequency converter 13i among the frequency converters 131 to 13N constitutes an up-converter with the corresponding i-th local oscillator 12i among the local oscillators 121 to 12N. The frequency conversion is performed on the i-th frequency comb signal supplied from the arbitrary waveform generator 11i with reference to the local oscillation frequency f _ci supplied from the local oscillator 12i, for example, to a microwave band of several GHz. Convert and output. The arbitrary waveform generators 111 to 11N, the local oscillators 121 to 12N, and the frequency converters 131 to 13N described above, together with the LPFs 141 to 14N and the two-input one-output multiplexers 151 to 15m, are frequency division components of the present invention. Multiple signal generating means is configured.

Each band of the up-converted N frequency comb signals output from the local oscillators 121 to 12N is a microwave band. However, as will be described later, the local oscillation frequencies f _{c1 to} f _cN are set. Therefore, the bandwidth of the N frequency comb signals after the up-conversion is the same as the bandwidth B of the HEMT amplifier 19 which is an example of the broadband amplifier in the present invention. The bandwidth is slightly smaller.

  The level attenuator 16, the multiplexing chips 171-1N, the circulator 18, and the HEMT amplifier 19 are accommodated in the cryogenic cooling device Cry and operate in a cryogenic environment. Each of the multiplexing chips 171 to 17N has the same configuration, and is input through a detection chip constituted by M superconducting detectors and M superconducting resonance circuits whose resonance frequency is variably controlled by a detection signal from the detection chip. It consists of a reading chip for reading out signals. Here, as an example, the multiplexing chips 171 to 17N have the same configuration as that of the multiplexing chip 50 shown in FIG. 8, respectively, and a detection chip 51 including M TESs as M superconducting detectors, The read chip 52 includes superconducting resonance circuits, and M superconducting resonance circuits and M TESs are individually connected by M coils 541 to 543 and the like. Each of the M superconducting resonance circuits is composed of an input coil, a SQUID, and a line. Further, as will be described later, the multiplexing chips 171 to 17N are connected by bonding wires so that signal lines for obtaining read signals are connected in cascade, and the transmittance at which the product of the respective transmittances is observed. It is supposed to be. The N × M TESs constituting the N detection chips 51 in all of the cascaded multiplexing chips 171 to 17N constitute a large-scale superconducting detector array.

  Further, the M superconducting resonance circuits in the readout chip of the multiplexing chip 171 have the first upconverted output from the LPF 141 out of the N × M peak frequency signals in the input frequency division multiplexed signal. The same frequency as the frequency signal of M peaks of the frequency division multiplexed signal is set as the resonance frequency. Similarly, the M superconducting resonance circuits in the readout chips of the multiplexing chips 172, 173,..., 17N are LPF 172 out of the N × M peak frequency signals in the input frequency division multiplexed signal. , 173,..., 17N output, the same frequency as the peak frequency signal of the second, third,.

The frequency converters 241 to 24N constitute a corresponding local oscillator and down-converter among the local oscillators 121 to 12N. That is, the i-th frequency converter 24i of the frequency converters 241 to 24N constitutes a down converter with the i-th local oscillator of the local oscillators 121 to 12N, and the BPFs 221 to 22N and the amplifier 231 are separated from the duplexers. The frequency division multiplexed signal in the microwave band supplied through ˜23N is frequency-converted with reference to the local oscillation frequency f _ci supplied from the local oscillator 12i, and a frequency composed of M frequencies in the baseband Downconverted into a division multiplexed signal and output. Therefore, the local oscillators 121 to 12N are shared by the up converter and the down converter. Each of the N signal processors 251 to 25N includes an A / D conversion unit. The BPFs 221 to 22N, the amplifiers 231 to 23N, the frequency converters 241 to 24N, and the local oscillators 121 to 12N constitute down-converting means that is a component of the present invention.

Next, the operation of this embodiment will be described.
The frequency converters 131 to 13N generate local oscillators 121 to 12N for the baseband frequency comb signal of the bandwidth A, which is output from the arbitrary waveform generators 111 to 11N and multiplexed with M peak frequency signals. Frequency conversion based on the local oscillation frequencies f _{c1 to} f _cN supplied from, and for example, outputs a signal up-converted to a microwave band of several GHz. The LPFs 141 to 14N pass only the fundamental wave components of the single side band of the microwave band output from the frequency converters 131 to 13N provided corresponding to the one-to-one, and remove unnecessary harmonic components. The fundamental wave component is a frequency comb signal with a bandwidth A up-converted to a microwave band.

FIG. 2A shows a frequency comb signal output from any one arbitrary waveform generator among the arbitrary waveform generators 111 to 11N. This frequency comb signal is a frequency comb signal having a line spectrum peak of the same power (level) at different M frequencies (M = 16 in this example). FIG. 2B shows an example of the frequency spectrum of the frequency comb signal up-converted to the microwave band output from the LPFs 141 to 14N. In FIG. 4B, f _{c1 to} f _cN indicated by dotted lines are local oscillation frequencies, and N discrete regions satisfying f _ci <f <(f _ci + A) indicated by rectangles with respect to the frequency f are increased. The bandwidth A of the converted frequency comb signal is shown. As shown in FIG. 2 (b), the frequency comb signal up-converted to the microwave band output from the LPFs 141 to 14N is not overlapped with each other by setting the local oscillation frequencies f _{c1 to} f _cN. In addition, the bandwidth of the entire N frequency band frequency comb signals can be increased to be equal to the bandwidth B of the HEMT amplifier 19.

  The frequency comb signals of N microwave bands with different frequency bands respectively extracted from the LPFs 141 to 14N are sequentially synthesized by the multiplexers 151 to 15m, and finally all of them are synthesized to have the bandwidth B. One frequency division multiplexed signal is output to one signal line (microwave coaxial line) L1. This input frequency division multiplexed signal of one signal line L1 is a frequency division multiplexed signal in the microwave band having the same amplitude peak at each of N × M different frequencies.

  The level attenuator 16 is provided for the purpose of attenuating room temperature noise to a level that does not affect the cryogenic system that handles weak signals. The level attenuator 16 also attenuates the input microwave band frequency division multiplexed signal of one signal line L1, and inputs the attenuated signal to the first stage multiplexing chip 171 among the N multiplexing chips 171 to 17N connected in cascade. The The multiplexing chip 171 detects the energy of photons or the like input from the outside by M TESs in the detection chip, and the resonance frequency of the M superconducting resonance circuits in the readout chip is slightly in accordance with the detection signal. Within the frequency range, and the phase and amplitude of the same frequency signal as the resonance frequency in the input microwave band frequency division multiplexed signal of the signal line L1 are changed and output. The resonance frequency of the M superconducting resonance circuits in the multiplexing chip 171 is the frequency of the M frequency signals of the first frequency comb signal described above, and the multiplexing chip 171 has an input microwave band frequency division multiplexing. The phase and amplitude of the same frequency signal as the M resonance frequencies of the first frequency comb signal in the signal are changed according to the detection result of the TES and output to the next multiplexing chip 172. By such modulation, an output spectrum obtained by multiplying the frequency comb signal shown in FIG. 2A by the transmittance shown in FIG. 2C is output from the multiplexing chip 171.

  Similarly, the multiplexing chip 172 detects the phases and amplitudes of the M frequency signals of the above-mentioned second frequency comb signal in the microwave frequency division multiplexed signal supplied from the multiplexing chip 171 as its detection chip. It is changed in accordance with the detection results of M TESs of which are output to the next multiplexing chip 173. Each of the multiplexed chips from the multiplexed chip 173 to the multiplexed chip 17N performs the same operation as described above.

  In this way, from the last stage multiplexing chip 17N among the N multiplexing chips 171 to 17N connected in cascade, the phase of each of N × M frequency signals different from each other is determined according to the TES detection result. Then, a frequency-division multiplexed signal (frequency comb signal) in the microwave band whose amplitude is changed is extracted.

  The frequency division multiplexed signal in the microwave band taken out from the multiplexing chip 17N at the final stage is supplied to the HEMT amplifier 19 through the circulator 18 and amplified, and then output to one signal line (microwave coaxial line) L2. Is done. That is, in this embodiment, the cryogenic cooling device Cry has only one input signal line (microwave coaxial line) L1, and only one output signal line (microwave coaxial line) L2. A microwave frequency division multiplexed signal (frequency comb signal) output via the signal line L2 is amplified by a low noise amplifier 20 operating in a room temperature environment, and then a 1-input 2-output type splitter 211. N distributed by ~ 21 m. The N-divided microwave band frequency division multiplexed signals are supplied to the BPFs 221 to 22N, respectively.

The BPFs 221 to 22N have their passbands discretely present at the frequency f _c1 <f <(f _cN + A) shown in FIG. 2B, and the signal bands of the frequency comb signals in the N microwave bands Only the frequency comb signal of one bandwidth A of the pass band assigned to itself is selected from the frequency division multiplexed signals of the bandwidth B that are set to the same band and output. That is, of the BPFs 221 to 22N, the i-th BPF 22i generates a frequency comb signal having an i-th bandwidth A in the range of frequency f _ci <f <(f _ci + A) from the frequency division multiplexed signal of the supplied microwave band. The frequency is selected and supplied to the i-th amplifier 23i. The amplifiers 231 to 23N are provided to compensate for a decrease in the signal-to-noise ratio associated with N distribution by the demultiplexers 211 to 21m of the frequency division multiplexed signal in the microwave band.

The frequency converter 241 performs frequency conversion based on the frequency division multiplexed signal in the microwave band input through the amplifier 231 and the local oscillation frequency f _c1 supplied from the local oscillator 121, and down-converts to the baseband band. The first frequency division multiplexed signal (frequency comb signal) of the bandwidth A thus generated is output. The down-converted first frequency comb signal is a demodulated signal of the frequency comb signal output from the multiplexing chip 171 and has a phase corresponding to the TES detection result of the multiplexing chip 171 at the frequency of M dips. And the amplitude has changed.

Similarly, the frequency converters 242, 243,..., 24N respectively include microwave frequency division multiplexed signals and local oscillators 122, 123,. ... Multiplexing chip 172 at the frequency of each of M dips that are frequency-converted with local oscillation frequencies f _c2 , f _{c3 ,.} , 173,..., 17N are demodulated to output the second, third,..., Nth frequency comb signals whose phases and amplitudes change according to the detection results of TES.

  The N signal processors 251 to 25N convert the baseband frequency comb signals supplied from the corresponding frequency converters 241 to 24N into digital signals. The computer (PC) 26 analyzes, for example, fast Fourier transform of digital signals supplied in parallel from the signal processors 251 to 25N to analyze changes in the phase and amplitude of the frequency signal of each dip, and obtains a TES detection result. . The detection result is stored as necessary. Here, the A / D converters in the signal processors 251 to 25N have the same narrowband A as the signals output from the arbitrary waveform generators 111 to 11N. If a commercially available product can be used and the dynamic range of the detection signal to be handled requires, for example, 14 bits, the bandwidth may be about 0.25 GHz which is the specification of the commercially available product.

On the other hand, according to the frequency multiplexing readout apparatus 10 of the present embodiment, the frequency division multiplexed signal in the microwave band supplied to the HEMT amplifier 19 is a signal obtained by frequency multiplexing N frequency comb signals, and FIG. The bandwidth B shown in FIG. 1 is in the range of 1 GHz to 10 GHz where the bandwidth of the HEMT amplifier 19 can be fully used. That is, if the band D of one pixel signal is 100 kHz and the ratio κ between adjacent resonance frequency intervals and D is “10”, the frequency multiplex readout apparatus 10 of this embodiment can calculate the number of theoretical pixels that can be multiplexed from the equation (1). M _p is
1 × 10 ³ ≦ M _p ≦ 1 × 10 ⁴
It is possible to read out an extremely high pixel signal (frequency division multiplexed signal).

  Further, according to the frequency multiplex reading device 10 of the present embodiment, the multiplexing chips 171 to 17N and the HEMT amplifier 19 in the cryogenic cooling device Cry have a single system configuration, and the cryogenic cooling device Cry and the outside room temperature are externally arranged. Since there are only two signal lines (microwave coaxial lines) L1 and L2 between the environment and the conventional apparatus which required 2N signal lines, the room temperature environment to the cryogenic cooling apparatus Cry Heat inflow through the signal line can be greatly suppressed.

  As described above, according to the frequency multiplex readout apparatus 10 of the present embodiment, the possibility of an advanced analyzer using a large-scale superconductor detection array mounted on a small cryogenic refrigerator with low power consumption is opened. In addition, according to the frequency multiplex reading device 10 of the present embodiment, TES is used as a superconducting detector of the detection chips in the multiplexing chips 171 to 17N. Therefore, if the physical quantity can be converted into heat, electromagnetic waves, energy particles, etc. In principle, anything can be detected, and when used as an electromagnetic wave (photon) detector, the wavelength range to be detected is extremely wide. What has been demonstrated so far is operation in the range of nine digits, from millimeter waves on the long wavelength (low frequency) side to gamma rays on the short wavelength (high frequency) side. In particular, in the X-ray region, there is an actual detection example in which the energy of each photon incident on the sensor is 30 times better than that of the semiconductor detector.

Next, the characteristics of the frequency multiplexing method using a superconducting resonator and a plurality of local oscillation frequencies will be described.
It has been reported that the surface resistance of the superconducting metal in the microwave band is two orders of magnitude smaller than that of a good conductor such as copper. Using this feature, research and development for applying a superconducting microwave filter having a steep frequency characteristic to a portable radio base station has been actively conducted in various countries. The superconducting resonator on the multiplexing chip in the frequency multiplex readout device of the present invention applies the principle of a superconducting filter that exhibits extremely low electrode loss and high frequency separation in the microwave band.

  The frequency multiplexing method has been widely used in the communication field. However, due to the steepness of the frequency characteristics of the filter used for carrier frequency discrimination, the frequency width between adjacent carriers and the number of multiplexed pixels in the unit readout band are different. Has a fate that is constrained. For this reason, simply setting a plurality of modulation / demodulation local oscillation frequencies limits the frequency discrimination of the normal metal filter, and as a result, it is impossible to dramatically increase the number of multiplexed pixels in the unit readout band. There was a problem. On the other hand, frequency multiplexing using only a superconducting filter with steep frequency characteristics can increase the number of multiplexed pixels at extremely low temperatures. However, the room temperature processing system has the A / D converter band limitation described above. Therefore, the total number of multiplexed pixels cannot be increased. On the other hand, according to the present invention, since the superconducting resonator and the modulation / demodulation of multiple frequencies are combined as in the above embodiment, the number of multiplexed pixels in the total signal processing system from cryogenic temperature to room temperature is reduced. A dramatic increase can be achieved.

Next, a cascade connection method for a plurality of multiplexed chips in the present invention will be described.
FIG. 3 shows an example of a cascade connection method of multiplexed chips in the present invention. In FIG. 3, N multiplexing chips 31 to 3N are mounted on a single board 40 to constitute a module 41. The multiplexing chips 31 to 3N are sequentially connected by a pair of bonding wires or the like in the module 41 so that the respective microwave readout lines are connected in cascade. The input of the first stage multiplexing chip 31 is connected to the input side coaxial cable 44 by a pair of bonding wires 431, and the output of the last stage multiplexing chip 3N is connected to the output side coaxial cable 45 by a pair of bonding wires 432. . Each of the multiplexing chips 31 to 3N has M (= M _p / N) superconducting resonance circuits. The multiplexing chips 31 to 3N correspond to the multiplexing chips 171 to 17N in FIG.

  According to this configuration, the modulation signals (up-converted signals) of the frequency comb signals from the N arbitrary waveform generators 111 to 11N supplied to the input side coaxial cable 44 are supplied to the multiplexing chips 31 to 3N. It is taken out from the output side coaxial cable 45 via the sequential. The transmittance of this configuration is the product of the transmittance of each of the multiplexing chips 31 to 3N.

Next, another embodiment of the frequency multiplex readout apparatus according to the present invention will be described.
FIG. 4 shows a configuration diagram of a main part of a second embodiment of the frequency multiplexing readout apparatus according to the present invention. In the figure, the same components as those in FIG. In the second embodiment of the frequency multiplexing read apparatus according to the present invention, each of the N multiplexing chips 171 to 17N in the configuration diagram of the embodiment shown in FIG. 1 is changed to the multiplexing chip 670 shown in FIG. This is the configuration. In FIG. 4, a multiplexing chip 670 includes M superconductor microwave dynamic inductance detectors (MKIDs) 681 to 68M (only three are shown in FIG. 4) and M capacitors 691. ˜69M (only three are shown in FIG. 4) and M lines 610-61M (only three are shown in FIG. 4), which are accommodated in the cryogenic cooling device 60. The MKID 681 constitutes a first superconducting resonance circuit connected to the connection point between the lines 610 and 611 via the capacitor 691. Similarly, the MKID 682 is connected to the connection point between the lines 611 and 612 via the capacitor 692 to form a second superconducting resonance circuit, and the MKID 683 is connected to the connection point between the lines 612 and 613 via the capacitor 693. A third superconducting resonance circuit is configured.

  The multiplexing chip 670 in the present embodiment has a configuration in which a detection chip and a reading chip using a known MKID that is a superconducting detector are shared. The superconductors MKID681 to 68M are normally associated with electrical resistance when a photon or particle having an energy larger than the intrinsic energy of the superconductor is incident, the superconducting electron pair flowing at zero electrical resistance in the superconducting thin film is broken. It is known that conduction electrons (quasiparticles) are excited and the value of the superconducting thin film inductance (dynamic inductance component without magnetic field) changes with the number of quasiparticle excitations. Based on this principle, the MKIDs 681 to 68M operate as quantum (non-thermal) detectors capable of energy spectroscopy such as incident photons.

  For this reason, the resonance frequency of the M superconducting resonance circuits composed of the MKIDs 681 to 68M and the capacitors 691 to 69M corresponds to the incidence of photons or particles having energy larger than the intrinsic energy of the superconductor to the MKIDs 681 to 68M. Change. Here, the M superconducting resonance circuits are set to different resonance frequencies, and a predetermined M frequency division multiplexed signals in the input microwave band (M = 3 in FIG. 4). The frequency signal is set to the same frequency as the frequency signal shown in FIG. The frequency multiplex reading apparatus of this embodiment has a configuration in which each of the multiplexing chips 171 to 17N in FIG. 1 is configured by the multiplexing chip 670 shown in FIG.

As a result, in the frequency division multiplex reading apparatus according to the present embodiment, for the N multiplexed chips 670 connected in cascade, the microwave band having the same amplitude peak at each of different N × M frequencies. When a frequency comb signal is input, a frequency comb signal in which the phase and amplitude of the N × M frequency signals are changed according to the incidence of photons on the N × M MKIDs is output. Since MKID does not require a bias current to flow unlike TES, this embodiment has an advantage that the bias line required in the above-described embodiment using TES in the detection chip is unnecessary. The MKID operates as a detector for electromagnetic waves and energetic particles having a frequency higher than that of the typical superconductor gap energy, millimeter wave and submillimeter wave (10 ¹¹ Hz), and is comparable to TES in the millimeter wave region. Sensitivity was demonstrated.

Next, a third embodiment of the frequency multiplex readout apparatus according to the present invention will be described.
FIG. 5 shows a configuration diagram of a detection chip 51B, which is a main part of the multiplexing chip, in the third embodiment of the frequency multiplex reading apparatus according to the present invention. In the figure, the same components as those in FIG. The third embodiment of the frequency multiplex readout apparatus according to the present invention has the configuration shown in FIG. 8 for each of the N multiplexing chips 171 to 17N in the configuration diagram of the embodiment shown in FIG. Instead of the detection chip 51, a detection chip 51B shown in FIG. 5 is used. That is, in this embodiment, each of the multiplexing chips 171 to 17N has the same configuration as the multiplexing chip 50 shown in FIG. 8, but the detection chip is not the 51 of FIG. 8 but the detection chip 51B shown in FIG. It is what is used.

The detection chip 51B shown in FIG. 5 includes a first coil of a superconductor in which a thin film having a strong magnetic susceptibility is magnetically coupled, and a second coil of a superconductor in which the thin film is not coupled. A configuration of a known metal magnetic calorimeter (MMC), which is an example of a superconducting detector, is formed with a total of M parallel circuits with coils (only three of which are shown in FIG. 5). ing. In FIG. 5, one connection point where the first coil L _S1L and the second coil L _S1R are connected in parallel is connected to one end (terminal opposite to the reading chip 52) of the coil 541 shown in FIG. The other connection point is connected to one end (terminal opposite to the reading chip 52) of the input coil 551 shown in FIG. Similarly, one of the connection points of the first coil L _S2L and the second coil L _S2R is connected to one end (terminal opposite to the readout chip 52) of the coil 542 shown in FIG. 8, and the other connection point is 8 is connected to one end (terminal opposite to the reading chip 52) of the input coil 552 shown in FIG. 8, and one of the connection points of the first coil L _S3L and the second coil L _S3R is shown in FIG. One end of the coil 543 (terminal opposite to the read chip 52) is connected, and the other connection point is connected to one end (terminal opposite to the read chip 52) of the input coil 553 shown in FIG. Others are the same.

In the detection chip 51B, a thin film (paramagnetic material) having a strong temperature-dependent magnetic susceptibility is caused to function as a photon absorber. The first and second coils connected in parallel form differential (difference) coils with equal self-inductance values, and apply a uniform magnetic field to these coils. When electromagnetic waves (photons) are incident on the differential coil in this state, only the first coil (L _S1L , L _S2L , L _S3L, etc.) to which the thin film (paramagnetic material) that causes a temperature rise is magnetically coupled. An inductance change caused by the energy of the incident photon occurs, and the inductance value of the second coil (L _S1R , L _S2R , L _S3R, etc.) does not change. Accordingly, the differential coil that cancels out when no photon is incident and does not generate an output generates an output reflecting the energy of the incident photon when the photon is incident. By using the metal magnetic calorimeter that performs such an operation as the detection chip 51B, the M superconducting resonance circuits constituting the readout chip 52 have M resonance frequencies in the corresponding detection chip 51B. Change independently of each other according to the incidence of photons on the differential coils.

  Therefore, in the frequency multiplexing readout apparatus of this embodiment, the detection chips 51B shown in FIG. 5 are used as the detection chips of the multiplexing chips 171 to 17N in FIG. The phase and amplitude of the N × M frequency signals of the input frequency comb signal in the microwave band can be changed and output according to the incident energy of the photons to the N × M metal magnetic calorimeters. . The metal magnetic calorimeter is a thermal detector that can detect anything in principle, such as electromagnetic waves and energetic particles, as long as it is a physical quantity that can be converted into heat. The best value of energy resolution in the X-ray region is the TES It is known that experimental results comparable to the best values can be obtained.

Next, a fourth embodiment of the frequency multiplex readout apparatus according to the present invention will be described.
FIG. 6 shows a block diagram of the main part of a multiplexing chip in the fourth embodiment of the frequency multiplexing read apparatus according to the present invention. In the figure, the same components as those in FIG. In the fourth embodiment of the frequency multiplex readout apparatus according to the present invention, the detection chips of the N multiplexing chips 171 to 17N in the configuration diagram of the embodiment shown in FIG. Instead of the detection chip 51, a detection chip 51C shown in FIG. 6 is used. That is, in this embodiment, each of the multiplexing chips 171 to 17N has the same configuration as the multiplexing chip 50 shown in FIG. 8, but the detection chip is not 51 shown in FIG. 8 but the detection chip 51C shown in FIG. It is what is used.

  A detection chip 51C shown in FIG. 6 has a configuration of a known SQUID magnetometer, which is an example of a superconducting detector, including a total of M detection coils such as detection coils L1, L2, and L3. The SQUID magnetometer is an electronic element in which a superconducting loop including a superconducting detection coil is magnetically coupled to a SQUID including one or two Josephson junction elements in the superconducting loop. Here, the detection coils L1, L2, and L3 shown in FIG. 6 correspond to the superconducting detection coil. 6, one end of the detection coil L1 is connected to one end (terminal opposite to the reading chip 52) of the coil 541 shown in FIG. 8, and the other end is one end of the input coil 551 shown in FIG. Connected to the opposite terminal). Similarly, one end of the detection coil L2 is connected to one end (terminal opposite to the reading chip 52) of the coil 542 shown in FIG. 8, and the other end is opposite to one end (opposite to the reading chip 52) of the input coil 552 shown in FIG. One end of the detection coil L3 is connected to one end of the coil 543 shown in FIG. 8 (terminal opposite to the readout chip 52), and the other end is one end of the input coil 553 shown in FIG. It is connected to (terminal opposite to the reading chip 52). Others are the same.

  In the present embodiment, when a signal magnetic field is applied to the M detection coils (L1 to L3, etc.) constituting the detection chip 51C, the magnetic flux linked to the detection coils (L1 to L3, etc.) is shown in FIG. The inductance values of the SQUID rings 571, 572, 573,. For this reason, the resonance frequency of the superconducting resonance circuit in the readout chip connected corresponding to the detection coil changes. Therefore, in the frequency multiplex reading apparatus of this embodiment, the detection chips 51C shown in FIG. 6 are used as the detection chips of the multiplexing chips 171 to 17N in FIG. Depending on the input intensity of the signal magnetic field to the N × M SQUID magnetometers for the input frequency comb signals in the microwave band having the same amplitude peaks at different N × M frequencies. Thus, the phase and amplitude of the N × M frequency signals can be changed and output. The SQUID magnetometer has the highest magnetic field resolution among the existing magnetic sensors, and is used for detection of weak magnetic fields generated from living bodies such as the brain, spinal cord, and heart, and a susceptibility meter.

Next, another example of a connection method of N multiplexed chips connected in cascade will be described. FIG. 7 shows another example of the cascade connection method of multiplexed chips in the present invention. The multiplex chip cascade connection method shown in FIG. 3 is modularized by cascading the respective microwave readout lines of the multiplex chips 31 to 3N each having M (= M _p / N) superconducting resonance circuits. It is a method to do. This is an effective method when the upper limit size of the multiplexed chip is limited by restrictions such as the irradiation size of the exposure apparatus.

  On the other hand, in the case of an exposure apparatus having a large irradiation area, as shown in FIG. 7, a set consisting of a detection chip and a reading chip connected by a coil corresponding to the upper limit value of the irradiation surface is N × M. One expansion multiplexing chip 300 integrated to form a cascade connection can be used on the board 46. That is, in the extended multiplexing chip 300, a multiplexing circuit unit in which M superconducting resonance circuits and M superconducting detectors are individually connected by M coils is shown by 3001 to 300N in FIG. In this way, there are N circuits in total, and the output terminals of the M superconducting resonance circuits of the multiplexing circuit section are connected to the input terminals of the M superconducting resonance circuits of the next multiplexing circuit section. . Such a configuration is also included in the cascaded multiplexed chips of the present invention.

  In the configuration of the cascaded multiplex chips shown in FIG. 3, N + 1 pairs of bonding wires for cascading the microwave readout lines are required for the connection between the multiplex chips, which is troublesome to mount. On the other hand, in the configuration of the extended multiplexing chip 300 shown in FIG. 7, since the microwave readout lines are cascaded and completed within the chip, the bonding wires are connected between the input terminal 47 of the chip and the board 46, and There is an advantage that only a total of two connections between the output terminal 48 of the chip and the board 46 are required.

  In FIG. 3, the cascade-connected multiplexed chips are arranged in a straight line, but the present invention is not limited to such an arrangement, and the shape and dimensions of the cryogenic stage and the peripheral components Arbitrary arrangements other than a straight line are also possible depending on arrangement restrictions. On the other hand, in FIG. 4, the cascaded multiplexed chips are arranged two-dimensionally in a plurality of rows and a plurality of columns. This assumes that the chip size is obtained up to the upper limit of the irradiation area of the circle or square of the exposure apparatus. For this reason, the present invention is not limited to the arrangement shown in FIG. 4, and the multiplexed chips are arranged within a circular or square irradiation surface.

  The present invention is not limited to the above embodiment. For example, a superconducting detector other than a TES, MKID, MMC, or SQUID magnetometer can be used as a detection chip in a multiplexing chip.

  The possibility of an advanced measurement analyzer using a large-scale superconductor detection array in which the frequency multiplex readout device of the present invention is mounted on a small-sized and low power consumption cryogenic refrigerator is opened.

10 Frequency multiplexing readout device 16, 741-74N Level attenuator 18, 751-75N Circulator 19, 62, 621-62N HEMT amplifier 20, 761-76N Low noise amplifier 26, 79 Computer (PC)
31 to 3N, 50, 171 to 17N, 31 to 3N, 501 to 50N, 670 Multiplexing chip 40, 46 Board 41 Module 44 Input side coaxial cable 45 Output side coaxial cable 47 Chip input terminal 48 Chip output terminal 51, 51B, 51C Detection chip 52 Reading chip 60, Cry Cryogenic cooling device 64 Microwave signal generation source 65 DC signal sources 111-11N, 711-71N Arbitrary waveform generators 121-12N, 731-73N, local oscillators 131-13N Frequency Converter (single sideband mixer)
141-14N Low-pass filter (LPF)
151 to 15m 2-input 1-output multiplexer 211 to 21m 1-input 2-output duplexer 221 to 22N Bandpass filter (BPF)
231 to 23N Amplifiers 241 to 24N, 721 to 72N, 771 to 77N Frequency converter (mixer)
251-25N, 781-78N Signal processor 300 Extended multiplexing chips 431, 432 Bonding wires 531, 532, 533 Superconducting transition edge detector (TES)
541-543, 561-56M Coil 551-55M Input coil 571-57M Josephson junction 581-58M, 610, 611-61M, 63 Line 591-59M, 691-69M Capacitor 681-68M Microwave dynamic inductance detector (MKID) ; Microwave Kinetic Inductance Detector)
3001-300N Multiplexing circuit portion L _S1L , L _S2L , L _S3L First coil L _S1R , L _S2R , L _S3R Second coil L1- _L3 Detection coil

Claims (6)

A readout chip having M superconducting resonance circuits having different resonance frequencies (where M is a natural number of 2 or more), and the resonance frequencies of the M superconducting resonance circuits are independent of each other according to a detection signal. Multiplexing chips composed of M detection chips having M superconducting detectors to be changed are connected in cascade with different resonance frequencies from each other, where N is a natural number of 2 or more. A first frequency division multiplex signal in a high frequency band consisting of M × N frequency signals having the same frequency as the resonance frequency of the M × N superconducting resonance circuits in the readout chip is supplied, and M × N A cascaded multiplexing chip that outputs a second frequency division multiplexed signal in the high frequency band composed of the M × N frequency signals whose amplitude and phase are controlled in accordance with the detection signal of the superconducting detector;
A broadband amplifier for amplifying and outputting the second frequency division multiplexed signal output from the cascade connection multiplexing chip;
N baseband signals, which are signals of the first band in an arbitrary waveform in which M frequency signals are frequency-division-multiplexed, are generated by changing the frequencies of the frequency signals from each other, and the N baseband signals are generated. , Up-converting into N high-frequency signals having different bands in the high-frequency band, and frequency-division-multiplexing the N high-frequency signals after the up-conversion to obtain a total bandwidth of the wideband amplifier band. A frequency division multiplex signal generating means for generating a frequency division multiplex signal having a second band less than the width and supplying the frequency division multiplex signal to the cascade connection multiplexing chip as the first frequency division multiplex signal;
Signal distribution means for distributing the second frequency division multiplexed signal output from the broadband amplifier into N;
Down-converting the N second frequency division multiplexed signals distributed by the signal distribution means into N baseband signals in the first band composed of the M frequency signals having different frequencies. Conversion means;
N signal processors that perform A / D conversion on a corresponding baseband signal among the N baseband signals output from the down-conversion means, and whose bandwidth is equal to or less than the bandwidth of the input baseband signal And analysis means including a computer for analyzing the amplitude and phase of the N baseband signals based on the digital signals output from the N signal processors ,
The N oscillators defining reference frequencies for ensuring the frequency identity of the corresponding baseband signals generated in the up-conversion and the down-conversion,
The M × N superconducting detectors constituting the cascade multiplexing chip constitute a large-scale superconducting detector array, and the cascade multiplexing chip and the broadband amplifier operate in a cryogenic environment. In addition, the cascade connection multiplexing chip is supplied with the first frequency division multiplexed signal from the frequency division multiplexed signal generating means operating in a room temperature environment through one first signal line, and the broadband A frequency division multiplex reading apparatus, characterized in that the second frequency division multiplexed signal is supplied through an amplifier to the signal distribution means operating in a room temperature environment via one second signal line.   The first and second frequency division multiplexed signals in the high frequency band are microwave band signals composed of frequency comb signals in which line spectra having the same frequency as the resonance frequency of the M × N superconducting resonance circuits are arranged in a comb shape. 2. The frequency multiplex readout apparatus according to claim 1, wherein the frequency multiplex readout signal is a frequency division multiplex signal.   The cascaded multiplexing chip is configured such that N microwave dynamic inductance detectors that serve as the detection chip and the reading chip are cascaded as one multiplexing chip. The frequency multiplex readout apparatus according to claim 2.   3. The frequency multiplex readout apparatus according to claim 1, wherein the M superconductor detectors constituting the detection chip are M superconducting transition edge detectors.   3. The frequency multiplex readout according to claim 1, wherein the M superconductor detectors constituting the detection chip are metal magnetic calorimeters composed of M differential coils of the superconductor. apparatus.   In the M superconductor detectors constituting the detection chip, a superconducting loop including a superconductor detection coil is connected to the M superconducting resonance circuits having a Josephson junction constituting the readout chip. 3. The frequency multiplex readout apparatus according to claim 1, wherein M SQUID magnetometers are magnetically coupled separately.

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