JP6413466B2 - Thermoelectric conversion element - Google Patents

Description

  The present invention relates to a thermoelectric conversion element based on a spin Seebeck effect and an inverse spin Hall effect.

  Expectations for thermoelectric conversion elements are increasing as efforts to address environmental and energy issues toward a sustainable society are becoming more active. This is because heat is the most common energy source that can be obtained from any medium such as body temperature, sunlight, engine, industrial waste heat. Therefore, thermoelectric conversion elements are expected to become more important in the future in applications such as increasing the efficiency of energy use in a low-carbon society and supplying power to ubiquitous terminals and sensors.

Recent research has revealed the existence of the “Spin-Seebeck Effect” in magnetic materials. The spin Seebeck effect is a phenomenon in which, when a temperature gradient is applied to a magnetic material, a flow of spin angular momentum (spin flow) of electrons occurs in a direction parallel to the temperature gradient [Patent Document 1]. Patent Document 1 reports the spin Seebeck effect in a NiFe film that is a ferromagnet. In Non-Patent Documents 1 and 2, a magnetic insulator such as yttrium iron garnet (YIG, Y ₃ Fe ₅ O ₁₂ ) and a metal film are reported. The spin Seebeck effect at the interface is reported. The spin current generated by the temperature gradient is converted into a current by the inverse spin-Hall effect. The reverse spin Hall effect is a phenomenon in which a spin current is converted into a current by spin orbit coupling of a substance, and is significant in a substance having a large spin orbit interaction (eg, Pt, Au, etc.). To express.

  In recent years, "spin thermoelectric conversion", which converts the temperature gradient into current via spin by using both the spin Seebeck effect and the inverse spin Hall effect, has attracted attention. A new thermoelectric conversion element, "spin thermoelectric element" Development is expected.

  FIG. 11 shows the structure of the thermoelectric conversion element disclosed in Patent Document 1. A thermal spin current converter 102 is formed on the sapphire substrate 101. The thermal spin current conversion unit 102 has a laminated structure of a Ta film 103, a PdPtMn film 104, and a NiFe film 105. Further, a Pt electrode 106 is formed on the NiFe film 105, and both ends of the Pt electrode 106 are connected to terminals 107-1 and 107-2, respectively. In the thus configured spin thermoelectric element, the NiFe film 105 plays a role of generating a spin current from the temperature gradient by the spin Seebeck effect, and the Pt electrode 106 generates an electromotive force from the spin current by the reverse spin Hall effect. Play a role. Specifically, when a temperature gradient is applied in the in-plane direction of the NiFe film 105, a spin current is generated in a direction parallel to the temperature gradient due to the spin Seebeck effect. Then, a spin current flows from the NiFe film 105 to the Pt electrode 106, or a spin current flows from the Pt electrode 106 to the NiFe layer 105. In the Pt electrode 106, an electromotive force is generated in a direction orthogonal to the spin current direction and the magnetization direction of NiFe due to the reverse spin Hall effect. The electromotive force can be taken out from terminals 107-1 and 107-2 provided at both ends of the Pt electrode 106.

Further, as one method for producing a spin thermoelectric element, there is an organometallic decomposition method (MOD method: Metal Organic Decomposition) as described in Patent Document 2 (Republished Patent WO2012 / 108276). As shown in FIG. 12, a gadolinium gallium garnet (hereinafter referred to as “GGG”, the composition is Gd ₃ Ga ₅ O ₁₂ ) on a substrate 4 and a yttrium iron garnet in which a part of the Y site is replaced by Bi. ,. 'Bi _x: YIG "and denoted composition _{Bi x Y 3-x Fe 5} O 12) MOD solution that contains a spin coating a, Bi by sintering _x: the YIG film 12 Can be created. Further, a spin thermoelectric element can be formed by forming a Pt electrode 3 on this film by sputtering. By applying a temperature gradient ΔT in the perpendicular direction B of this element and applying a magnetic field in the in-plane direction C, the electromotive force can be taken out from the electrodes 7 and 9.

JP 2009-130070 Republished patent WO2012 / 108276

Uchida et al. “Spin Seebeck insulator”, Nature Materials, 2010 vol.9 p.894 Uchida et al. “Observation of longitudinal spin-seebeck effect in magnetic insulator”, Applied Physisc Letters, 2010, vol.97, p172505

  However, since the current output of the spin thermoelectric element is small and about several uV / K, it has not been put into practical use. For this reason, increasing the output of the spin thermoelectric element is a major issue. In order to increase the output of the spin thermoelectric element, it is necessary to develop a magnetic material capable of causing a large spin current to enter the metal film.

  An object of the present invention is to solve this problem and provide a thermoelectric conversion element capable of increasing output.

  The present invention is a thermoelectric conversion element having a magnetic layer that exhibits a spin Seebeck effect and an electromotive layer that exhibits a reverse spin Hall effect, wherein Ce, which has an orbital angular momentum quantum number L as the magnetic layer. A thermoelectric conversion element using a magnetic layer containing at least one element selected from the element group consisting of Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

  According to the present invention, it is possible to increase the output of the thermoelectric conversion element.

3 is a table showing orbital angular momentum quantum number L, spin angular momentum quantum number S, and atomic weight n of each element. It is the figure which showed the structure of the spin thermoelectric element of 1st embodiment of this invention. FIG. 3 is a diagram showing a structure of a spin thermoelectric element using an R ₁ : YIG magnetic layer, a Pt layer, and a GGG substrate. It is the figure which showed the relationship between orbital angular momentum quantum number L and the output of a spin thermoelectric element. It is the figure which showed the structure of the spin thermoelectric element of 2nd embodiment of this invention. It is the figure which showed the relationship between the spin angular momentum quantum number S and the output of a spin thermoelectric element. It is the figure which showed the structure of the spin thermoelectric element of 3rd embodiment of this invention. FIG. 6 is a diagram showing the relationship between atomic weight n and the output of a spin thermoelectric element. Yb ₁ described in Example: a diagram showing the structure of a spin thermoelectric element using the YIG magnetic layer. FIG. 4 is a diagram showing electromotive forces of a spin thermoelectric element using a YIG magnetic layer, a spin thermoelectric element using a Yb ₁ : YIG magnetic layer, and a spin thermoelectric element using a Bi ₁ : YIG magnetic layer. It is the figure which showed the structure of the spin thermoelectric element currently disclosed by patent document 1. FIG. It is the figure which showed the structure of the spin thermoelectric element currently disclosed by patent document 2. FIG.

[First embodiment]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[Description of structure]
FIG. 2 is a perspective view schematically showing the spin thermoelectric element of the first embodiment of the present invention. This spin thermoelectric element includes a magnetic layer (hereinafter referred to as R _L : YIG magnetic layer) 501 in which a part of the c site of YIG is replaced with an element R _L having an orbital angular momentum quantum number L, and a spin-orbit mutual relationship. The structure includes an electromotive layer (conductive layer) 502 made of an element having a large spin-orbit interaction. The element R _L having the orbital angular momentum quantum number L is Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, and the element having a large spin-orbit interaction is, for example, Au. , Pt, Ir, Bi, etc.

The thickness of this R _L : YIG magnetic layer 501 can be changed according to the application of thermoelectric power generation and the temperature range, but it is usually set to about several tens nm to several um, which is about the diffusion length of thermal magnon. Is desirable. In addition, the thickness of the electromotive layer 502 is preferably set to several nm to several hundred nm, which is about the spin diffusion length of the electromotive layer.

By applying a magnetic field in the x direction (in-plane direction) and a temperature gradient in the z direction (thickness direction) of this spin thermoelectric element, a spin current is generated in the z direction in the R _L : YIG magnetic layer by the spin Seebeck effect. Occur. When this spin current enters the electromotive layer 502, the spin current is converted into a current by the reverse spin Hall effect. Thereby, the electromotive force can be taken out from the terminal 503 and the terminal 504.
[Description of effects]
In the present embodiment, the efficiency of generating a spin current from the temperature gradient (spin current generation efficiency) is improved. By using a YIG magnetic layer in which an element having an orbital angular momentum quantum number L is substituted at the c site, the spin-lattice-interaction of the YIG magnetic layer increases and heat is more efficiently generated. From this, it becomes possible to generate a spin current. As a result, the spin flow rate generated in the YIG magnetic layer is increased, and the output of the spin thermoelectric element is improved.

As shown in FIG. 3, an R1: YIG magnetic film 601 in which YIG c-sites are partially substituted with various elements R on a GGG substrate 605, a Pt layer 602 formed thereon, and terminals 603 and 604 formed on the Pt layer 602 Thus, a spin thermoelectric element was produced. FIG. 4 shows the dependence of the output of the spin thermoelectric element and the orbital angular momentum quantum number L. Here, the various elements R are any one of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu shown in FIG. In FIG. 7, the composition ratio X of the element R in the R1: YIG magnetic film 601 (R _X Y _{3 -X} Fe ₅ O ₁₂ ) is all 1.

  The graph in FIG. 4 means that the white area has a higher probability of being in that state, and conversely, the black area has a lower probability of being in that state. In other words, FIG. 4 is a diagram comprehensively showing which output is most likely to be output in a certain orbital angular momentum quantum number L state. For example, when the orbital angular momentum quantum number L is 4.09, the output is near white at 0.327 (the white at the intersection of L = 4.09 and output 0.327 in FIG. 4). This is the case when L = 0.409. It shows that it is most likely to be 0.327. When L = 0, the output is the whitest around 0.2. This indicates that when L = 0, the output is most likely to be about 0.2. This white area is in a place where the output is low when L is small, and is in a place where the output is high when L is large, and it can be seen that L is better to obtain a large output. In FIG. 4, since the white region extends from the lower left to the upper right, it can be seen that there is a positive correlation between the orbital angular momentum quantum number L and the output of the spin thermoelectric element. This is because the spin-lattice interaction is increased by the orbital angular momentum quantum number L, and spin current is generated more efficiently from heat (spin current generation efficiency is improved).

As described above, in the spin thermoelectric element of the present embodiment, a part of the c-site of YIG is replaced by the element R _L (R _L = Ce, Pr, Nd, Sm, Eu, Tb, By using the R _L : YIG magnetic layer substituted with Dy, Ho, Er, Tm, Yb), the output of the spin thermoelectric element is improved.

In this embodiment, a part of the c site is replaced with the element RL, but the output of the spin thermoelectric element can be improved even if all of the c site is replaced. Depending on the manufacturing method, the original Y may remain slightly replaced, but the output can be improved even in that case.
[Description of manufacturing method]
Next, an example of a method for manufacturing the spin thermoelectric element of the present embodiment will be described with reference to FIG.

First, the R _L : YIG magnetic layer 601 is formed on the GGG substrate 605. The R _L : YIG magnetic layer 601 includes a portion of YIG c site (yttrium Y site) as an element R _L having an orbital angular momentum quantum number _L (R _L = Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb). R _L : YIG magnetic layer 601 is formed by sputtering, organometallic decomposition (MOD), sol-gel, ferrite plating, aerosol deposition (AD), PLD (Pulsed Laser Deposition), LPE (Liquid). A magnetic film may be formed on a substrate using Phase Epitaxy), or a sintered body or a single crystal may be used as a magnetic body as it is.

Next, on the R _L : YIG magnetic layer 501, an electromotive layer 502 made of an element having a large spin activation interaction (for example, Au, Pt, Ir, Bi, etc.) is formed. As a forming method, a sputtering method, a vapor deposition method, a plating method, a screen printing method, or the like can be used.

  By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, an electromotive force can be taken out from the terminal 503 and the terminal 504.

The method for manufacturing the spin thermoelectric element is merely an example, and the present invention is not limited to this.
[Second Embodiment]
A second embodiment of the present invention will be described in detail below with reference to the drawings.
[Description of structure]
FIG. 5 is a diagram schematically showing the spin thermoelectric element of this embodiment. This spin thermoelectric device has a magnetic layer (hereinafter referred to as “YIG”) in which a part of the c site of YIG is replaced by an element R _S having an orbital angular momentum quantum number L and a small (2 or less) spin angular momentum quantum number S. R _S : YIG (referred to as a magnetic layer) 801 and an electromotive layer (conductive layer) 802 made of an element having a large spin-start interaction.
Elements R _S with orbital angular momentum quantum number L and small spin angular momentum quantum number S (less than 2) are Ce, Pr, Nd, Ho, Er, Tm, Yb, and spin-initiated interaction Examples of the large element include Au, Pt, Ir, and Bi.

The thickness of this R _S : YIG magnetic layer 801 can be changed according to the application of thermoelectric power generation and the temperature range, but it is usually set to about several tens of nanometers to several um of the thermal magnon diffusion length. Is desirable. In addition, the thickness of the electromotive layer 802 is preferably set to several nm to several hundreds nm, which is about the spin diffusion length of the electromotive layer.

By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, a spin current is generated in the z direction in the R _S : YIG magnetic layer due to the spin Seebeck effect. When this spin current enters the electromotive layer 802, the spin current is converted into a current by the reverse spin Hall effect. Thereby, the electromotive force can be taken out from the terminal 803 and the terminal 804.
[Description of effects]
In this embodiment, the spin current transmission efficiency is improved. If an element with a large spin angular momentum quantum number S is present at the c-site of the YIG magnetic layer, the dipole-dipole-interaction or super at the YIG c-site (Y site) and the YIG a and d sites (Fe sites) -Exchange-interaction causes spin current to be scattered. Therefore, by using a YIG magnetic layer in which an element having a small spin angular momentum quantum number S (2 or less) is substituted at the c site, the spin current transfer efficiency is improved and the output of the spin thermoelectric element is improved.

As shown in FIG. 3, a spin thermoelectric element composed of an R ₁ : YIG magnetic film 601, a GGG substrate 605, and a Pt layer 602, in which a part of YIG c-site is partially substituted with various elements R _s , is created. The dependence of the output of the thermoelectric device and the spin angular momentum quantum number S was shown. Here, the various elements R are La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu shown in FIG. In FIG. 8, the composition ratio X of the element R in the R1: YIG magnetic film 601 (RXY3-XFe5O12) is all 1.

  The graph of FIG. 6 means that the white area has a higher probability of being in that state, and the black area has a lower probability of being in that state. In the graph, since the white region extends from the upper left to the lower right, it can be seen that there is a negative correlation between the spin angular momentum quantum number S and the output of the spin thermoelectric element. This is because if the spin angular momentum quantum number S is present at the c site, the spin current is scattered by the dipole-dipole-interaction or super-exchange-interaction of the c site of YIG and the a and d sites of YIG, This is because the spin current transmission efficiency is lowered.

As described above, in the spin thermoelectric element of this embodiment, part of the c site of YIG has an orbital angular momentum quantum number L and an element R _S having a small spin angular momentum quantum number S (2 or less). By using the R _S : YIG magnetic layer substituted with (R _S = Ce, Pr, Nd, Ho, Er, Tm, Yb), the output of the spin thermoelectric element is improved.

In this embodiment, a part of the c site is replaced with the element Rs, but the output of the spin thermoelectric element can be improved even if all of the c site is replaced. Depending on the manufacturing method, the original Y may remain slightly replaced, but the output can be improved even in that case.
[Description of manufacturing method]
Next, with reference to FIG. 5, the 1st example of the manufacturing method of the spin thermoelectric element of this embodiment is demonstrated.

First, a part of the YIG c site (yttrium Y site) has an orbital angular momentum quantum number L and a small spin angular momentum quantum number S (less than 2) element R _S (R _S = Ce , Pr, Nd, Ho, Er, Tm, and Yb), an R _S : YIG magnetic layer 801 is formed. The R _S : YIG magnetic layer 801 is formed on the substrate using sputtering, organometallic decomposition (MOD), sol-gel, ferrite plating, aerosol deposition (AD), PLD, LPE, etc. A magnetic film may be formed, or a sintered body or a single crystal may be used.

Next, on the R _s : YIG magnetic layer 801, an electromotive layer 802 made of an element having a large spin activation interaction (for example, Au, Pt, Ir, Bi, etc.) is formed. As a forming method, a sputtering method, a vapor deposition method, a plating method, a screen printing method, or the like can be used.

  By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, an electromotive force can be taken out from the terminal 803 and the terminal 804.

The method for manufacturing the spin thermoelectric element is merely an example, and the present invention is not limited to this.
[Third embodiment]
A third embodiment of the present invention will be described in detail below with reference to the drawings.
[Description of structure]
FIG. 7 is a diagram schematically showing the spin thermoelectric element of this embodiment. In this spin thermoelectric element, a part of the c site of YIG has an orbital angular momentum quantum number L, a small spin angular momentum quantum number (2 or less), and an element R having a large atomic weight n (155 or more) R _The structure includes a magnetic layer (hereinafter referred to as an R _n : YIG magnetic layer) 1001 substituted with _n and an electromotive layer (conductive layer) 1002 made of an element having a large spin-starting interaction. Elements R _n having an orbital angular momentum quantum number L, a small spin angular momentum quantum number (less than 2), and a large atomic weight n (greater than 155) are Ho, Er, Tm, Yb, and spin Examples of the element having a large activation interaction include Au, Pt, Ir, and Bi.

The thickness of this R _n : YIG magnetic layer 1001 can be changed according to the application of thermoelectric power generation and the temperature range, but it is usually set to about several tens nm to several um, which is about the diffusion length of thermal magnon. Is desirable. The thickness of the electromotive layer 1002 is preferably set to several nm to several hundred nm, which is about the spin diffusion length of the paramagnetic material.

By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, a spin current is generated in the z direction in the R _n : YIG magnetic layer due to the spin Seebeck effect. When this spin current enters the electromotive layer 1002, the spin current is converted into a current by the inverse spin Hall effect. Thereby, the electromotive force can be taken out from the terminal 1003 and the terminal 1004.
[Description of effects]
In this embodiment, the temperature gradient applied to the YIG magnetic layer can be increased. By using a YIG magnetic layer in which an element having a large atomic weight n (155 or more) is substituted at the c site, phonon scattering in the YIG magnetic layer increases, and the thermal conductivity κ decreases. Therefore, the temperature gradient applied to the YIG magnetic layer is increased, and the output of the spin thermoelectric element is improved.

As shown in FIG. 3, a spin thermoelectric element composed of an R ₁ : YIG magnetic film 601, a GGG substrate 605, and a Pt layer 602 in which YIG c sites are partially substituted with various elements R is prepared. The dependence of atomic weight n on the output of the device is shown. Here, the various elements R are La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu shown in FIG. The graph of FIG. 8 means that the white region has a higher probability of being in that state, and conversely, the black region has a lower probability of being in that state. In FIG. 10, the composition ratio X of the element R in the R1: YIG magnetic film 601 (RXY3-XFe5O12) is all 1.

In the graph, since the white region extends from the lower left to the upper right, it can be seen that there is a positive correlation between the atomic weight n and the output of the spin thermoelectric element. By substituting an element with a large atomic weight n, the difference in atomic weight between the element to be substituted and the substituting element increases, and phonon scattering increases. As a result, the thermal conductivity κ is reduced and the temperature gradient applied to the R _n : YIG magnetic layer is increased, so that the output of the spin thermoelectric element is improved.

As described above, in the spin thermoelectric element of this embodiment, a part of the c site of YIG has orbital angular momentum quantum number L, spin angular momentum quantum number S is small (2 or less), and atomic weight n The output of the spin thermoelectric element is improved by using the R _n : YIG magnetic layer substituted with a large Rn (155 or more) element R _n (R _n = Ho, Er, Tm, Yb, Lu).

In the present embodiment, a part of the c site is substituted with the element Rn, but the output of the spin thermoelectric element can be improved even if all of the c site is substituted. Depending on the manufacturing method, the original Y may remain slightly replaced, but the output can be improved even in that case.
[Description of manufacturing method]
Next, with reference to FIG. 7, the 1st example of the manufacturing method of the spin thermoelectric element of this embodiment is demonstrated.

First, a part of YIG c site (yttrium Y site) has orbital angular momentum quantum number L, spin angular momentum quantum number S is small (2 or less), and atomic weight n is large (155 or more). ) element _{R n (R n = Ho,} Er, Tm, Yb, R n substituted with Lu): creating a YIG magnetic layer 1001. R _n : YIG magnetic layer 1001 is formed on the substrate by sputtering, organometallic decomposition method (MOD method), sol-gel method, ferrite plating method, aerosol deposition method (AD method), PLD method, LPE method, etc. Alternatively, a magnetic film may be formed, or a sintered body or a single crystal may be used.

  Next, on the magnetic layer 1001, an electromotive layer 1002 made of an element having a large spin activation interaction (for example, Au, Pt, Ir, Bi, etc.) is formed. The shape is a film shape using a sputtering method, a vapor deposition method, a plating method, a screen printing method, or the like.

  By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, an electromotive force can be taken out from the terminal 1003 and the terminal 1004.

Moreover, the manufacturing method of the said spin thermoelectric element is a mere example, and is not limited to this.
(Other embodiments)
In the above embodiment, only one kind of element is substituted. However, when multiple types of substitution are performed, phonon scattering in the magnetic material is enhanced and the thermal conductivity is lowered. As a result, the temperature gradient applied to the magnetic material increases and the output increases.

  In the above embodiment, a YIG magnetic layer is used as the magnetic layer. However, the present invention is not limited to this, and garnet ferrite (YIG), spinel ferrite, magnetoplumbite, corundum, perovskite, rutile, and the like can be used as the oxide magnetic body. In addition to oxides, magnetic metals, magnetic nitrides, magnetic sulfides, and the like that exhibit magnetism can be used.

FIG. 9 shows the shape of a spin thermoelectric element using a Yb ₁ : YIG magnetic layer in which a part of the c site of YIG is replaced with Yb.

First, the Yb ₁ : YIG magnetic layer 1201 is formed on the GGG substrate 1205 by the organometallic compound decomposition method (MOD method). The subscript of Yb means the number of elements to be substituted, and Yb1: YIG = Yb1Y2Fe5O12. The procedure for creating the magnetic layer 1201 is as follows. A MOD material solution of Yb1: YIG is applied onto the GGG substrate 1205 with a spin coater. For example, when Y is replaced by 10% with Yb, a MOD material solution of Yb: Y = 9: 1 is used. Then, it is dried to remove the organic solvent. Next, temporary baking is performed to decompose and volatilize the organic matter. Finally, firing is performed to convert to oxide and crystallize.

  The same applies to the case where a magnetic layer entirely substituted with Yb is formed, and the proportion of Yb in the MOD material solution may be increased.

Next, a Pt layer 1202 is formed on the Yb ₁ : YIG film 1201 formed on the GGG substrate 1205 by a sputtering method.

Through the above procedure, a spin thermoelectric element using a Yb ₁ : YIG magnetic layer in which a part of the c site of YIG is replaced with Yb can be produced. By applying a magnetic field in the x direction and a temperature gradient in the z direction of the spin thermoelectric element, an electromotive force can be taken out from the terminal 1203 and the terminal 1204.

FIG. 10 shows a spin thermoelectric element (Pt / Yb ₁ : YIG / GGG) using the Yb ₁ : YIG magnetic layer prepared in the above procedure and a spin thermoelectric element (Pt / Yb ₁ : YIG / GGG) using the Bi ₁ : YIG magnetic layer. / Bi ₁ : YIG / GGG) and a comparison of electromotive forces of spin thermoelectric elements (Pt / YIG / GGG) using a YIG magnetic layer. The horizontal axis of the graph represents the magnitude of the magnetic field applied in the x-axis direction, and the vertical axis represents the electromotive force generated when a temperature difference ΔT = 8K is applied in the z-direction. The Pt / Yb ₁ : YIG / GGG spin thermoelectric element generates an electromotive force of about 5 uV, and the Pt / Bi ₁ : YIG / GGG spin thermoelectric element generates an electromotive force of about 3 uV. In the Pt / YIG / GGG spin thermoelectric element, an electromotive force of about 2 uV is generated. Therefore, it is understood that the output of the spin thermoelectric element is improved by substituting a part of the c site of YIG with Yb.

A spin thermoelectric element (Pt / Er ₁ : YIG / GGG) using an Er ₁ : YIG magnetic layer was also produced, and the same results as Yb and Bi were obtained. In these examples, the number of substituting elements is all 1, but the output of the spin thermoelectric element is improved when it is 0.1 or more.

502, 802, 1002 electromotive layer
503, 504, 603, 604, 803, 804, 1003, 1004, 1203, 1204 terminals
501, 601 R _L : YIG magnetic layer
602, 1202 Pt layer
605, 1205 GGG substrate
801 R _S : YIG magnetic layer
1001 R _n : YIG magnetic layer
1201 Yb: YIG magnetic layer

Claims (7)

A thermoelectric conversion element having a magnetic layer that exhibits a spin Seebeck effect and an electromotive layer that exhibits a reverse spin Hall effect,
YIG (yttrium iron garnet) is used as the magnetic layer, and the c-site of YIG is replaced by an element R _L having an orbital angular momentum quantum number _L (R _L = Pr, Nd, Sm, Dy , Ho, Er, Tm, A thermoelectric conversion element using a magnetic layer partially substituted with at least one element selected from Yb ) . A thermoelectric conversion element having a magnetic layer that exhibits a spin Seebeck effect and an electromotive layer that exhibits a reverse spin Hall effect,
YIG is used as the magnetic layer , and almost all of the elements occupying the c-site of YIG have Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, orbital angular momentum quantum number L. A thermoelectric conversion element substituted with at least one element selected from the element group consisting of Yb. Wherein among the elemental was replaced partially at least one element in the YIG the c site spin angular momentum quantum number S is selected from 2 the following elements Rs (Rs = Pr, Nd, Ho, Er, Tm, Yb) The thermoelectric conversion element according to claim 1, wherein a magnetic layer is used. A thermoelectric conversion element having a magnetic layer that exhibits a spin Seebeck effect and an electromotive layer that exhibits a reverse spin Hall effect,
YIG is used as the magnetic layer, and almost all of the elements occupying the c-site of YIG are made of an element group consisting of Ce, Pr, Nd, Ho, Er, Tm, and Yb having a spin angular momentum quantum number S of 2 or less. A thermoelectric conversion element that is at least one element selected. Among the elemental atomic weight n is 155 or more elements Rn: (Rn = Ho, Er , Tm, consisting Yb elemental) or al magnetic body partially substituted the YIG of c site with at least one element selected The thermoelectric conversion element of Claim 3 which uses a layer. A thermoelectric conversion element having a magnetic layer that exhibits a spin Seebeck effect and an electromotive layer that exhibits a reverse spin Hall effect,
YIG is used as the magnetic layer, and almost all elements occupying the c-site of YIG are at least one element selected from the group consisting of Ho, Er, Tm, Yb, and Lu with an atomic weight n of 155 or more. Thermoelectric conversion element. The element R _L, thermoelectric conversion element according to claim 1, 3 or 5 composition ratio X of _{R X Y 3-x Fe 5} O 12 obtained by substituting c site of the YIG by Rs or Rn is 0.1 or more.