Magnetic memory element and magnetic memory device

Abstract

A magnetic memory element comprises an altermagnet layer that is composed of a magnetic body having a magnetic order in which time inversion symmetry is broken. In the magnetic body, a crystal structure defined by a combination of a space group and Wyckoff positions of magnetic ions is P63 / mmc and 2a, P-62c and 12i, or Pnma and 4, and the magnetic ions exhibit an antiparallel spin arrangement. An example of such a magnetic body is FeS which has a NiAs structure, and in which the space group is P63 / mmc and the Wykoff positions of Fe ions are 2a.

Description

Magnetic memory mechanism and magnetic memory device

[0001] The present invention relates to a magnetic memory element and a magnetic memory device.

[0002] Current magnetic memory devices use ferromagnetic materials in which electron spins are aligned in parallel. As shown in Figure 1, ferromagnetic materials can switch between an up-spin state (e.g., "0" state) and a down-spin state (e.g., "1" state) through a time-reversal operation, making the two spin states distinguishable. Magnetic memory devices using ferromagnetic materials utilize the breaking of the time-reversal symmetry of the ferromagnetic material to retain and control information (see, for example, Patent Document 1).

[0003] U.S. Patent No. 9,837,602

[0004] However, ferromagnetic materials have high magnetization, which presents the following problems: (i) Leakage magnetic fields originating from magnetization cause interference between bits, hindering high integration. (ii) Response speed is relatively slow. (iii) Information can be lost due to magnetic disturbances.

[0005] On the other hand, typical antiferromagnets, in which electron spins are arranged antiparallel, are known to have low leakage magnetic fields, fast response times, and resistance to magnetic disturbances. As shown in Figure 2, in such antiferromagnets, although the ↑↓ spin state and the ↓↑ spin state switch to each other through time reversal, these two spin states coincide through translation and become indistinguishable. Therefore, antiferromagnets are considered unsuitable for magnetic memory elements.

[0006] This invention has been made in view of the above problems, and aims to provide a magnetic memory element and a magnetic memory device that read and write information using a new magnetic material.

[0007] The magnetic memory element according to the present invention has a crystal structure defined by a combination of space group and Wyckoff position of magnetic ions, P6 ３The altermagnet layer comprises a magnetic material which is one of the following: / mmc and 2a, P-62c and 12i, and Pnm and 4c, and in which the magnetic ions exhibit an antiparallel spin arrangement and have a magnetic order in which time-reversal symmetry is broken.

[0008] The magnetic memory device according to the present invention comprises a plurality of magnetic memory elements, each of which is defined as a magnetic memory element comprising the alter magnet layer described above.

[0009] According to the present invention, by using a magnetic material that exhibits an antiparallel spin arrangement in a special crystal structure and has a magnetic order with broken time-reversal symmetry, it is possible to realize a magnetic memory element with low leakage magnetic field, fast response, and high resistance to magnetic disturbances.

[0010] This is a schematic diagram illustrating the breaking of time-reversal symmetry in ferromagnets. This is a schematic diagram illustrating the time-reversal symmetry in a typical antiferromagnet. This is a schematic diagram illustrating the breaking of time-reversal symmetry in the alter magnet of this embodiment. This is a schematic diagram illustrating the spontaneous Hall effect in ferromagnets and alter magnets. This is a schematic diagram showing the crystal structure (NiAs structure) of FeS and an antiparallel spin arrangement. This is a schematic diagram showing the NiAs structure and the Troilite structure as crystal structures of FeS. This is a graph showing the magnetic field dependence of magnetization and Hall resistivity of FeS at 300K. This is a schematic diagram showing the crystal structure of MnPtAl and an antiparallel spin arrangement. This is a graph showing the magnetic field dependence of magnetization and Hall conductivity of MnPtAl at various temperatures. This is a graph showing the temperature dependence of magnetization of MnPtAl. This is a schematic diagram showing the NiAs structure and its derived structures as crystal structures of the alter magnet. This is a schematic diagram showing the configuration of a magnetic memory element with a hole bar structure according to Example 1. This is a schematic diagram showing the configuration of a magnetic memory element of an SOT-MRAM according to Example 2. This is a schematic diagram showing the configuration of a magnetic memory element of an STT-MRAM according to Example 3. This is a schematic diagram for explaining a readout method using X-ray magnetic circular dichroism (XMCD) according to Example 4. This is a graph showing the measurement results of XMCD at room temperature for FeS. This is a graph showing the magnetic field dependence of the FeS readout signal.

[0011] Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, AlterMagnet is presented as a new magnetic material to be used in a magnetic memory element.

[0012] As shown in Figure 3, in the alter magnet of this embodiment, the magnetic ions exhibit an antiparallel spin arrangement, while the non-magnetic ions are positioned in a staggered pattern. The ↑↓ state ("0") and the ↓↑ state ("1") switch to each other through the time reversal operation, but thanks to the non-magnetic ions, the two spin states do not coincide under the translation operation. In this way, the alter magnet can distinguish between the two spin states and breaks time reversal symmetry.

[0013] Because ferromagnetic materials exhibit a broken time-reversal symmetry, a spontaneous Hall effect proportional to the magnetization M is observed at zero magnetic field, as shown in Figure 4. The spontaneous Hall effect is a phenomenon in which an electromotive force is generated in a direction perpendicular to the electric current. On the other hand, in conventional typical antiferromagnetic materials, the net magnetization is zero, so the spontaneous Hall effect does not occur.

[0014] As shown in Figure 4, in an alternator magnet, even if the net magnetization is zero, the presence of a virtual magnetic field originating from the quantum phase can cause a spontaneous Hall effect proportional to the virtual magnetic field at zero magnetic field. In the ↑↓ state ("0") and the ↓↑ state ("1") of the alternator magnet, the direction of the virtual magnetic field is opposite, so the sign of the spontaneous Hall effect is opposite. Therefore, it is thought that the two spin states can be electrically distinguished and read out by the spontaneous Hall effect.

[0015] Figure 5A shows an example of an alter magnet, specifically the NiAs structure, one of the crystal structures of FeS, and the antiparallel spin arrangement of Fe. The NiAs structure of FeS has a hexagonal crystal structure, in which layers of iron (Fe) and triangular lattice layers of sulfur (S) are alternately stacked in the

[001] direction (z direction). The triangular lattice layers of nonmagnetic S ions are arranged in a staggered pattern, and each Fe ion is sandwiched between a pair of triangular lattice layers.

[0016] Figure 5B shows the NiAs structure in the high-temperature phase and the troilite structure in the low-temperature phase as crystal structures of FeS. At high temperatures, FeS has a space group of P6. ３ At / mmc, the Fe ion's Wyckoff position is 2a, forming a NiAs structure. At low temperatures (below 400K), the Fe ion's position shifts slightly, and the space group transitions to P-62c, with the Fe ion's Wyckoff position being 12i, forming a troilite structure.

[0017] FeS is an antiferromagnetic semiconductor with a magnetic order temperature of 576 K. Figure 6 shows the magnetization M and Hall resistivity ρ of FeS at 300 K. ｙｘ The measurement results of the magnetic field dependence are shown. Here, a magnetic field B was applied parallel to

[001] , and a current I was passed perpendicular to

[001] . The magnetization M changed almost linearly with respect to the magnetic field B, while the Hall resistivity ρ ｙｘFrom the profile, it can be seen that the spontaneous Hall effect is observed in a zero magnetic field. This means that the ↑↓ state and the ↓↑ state can be electrically distinguished and read out at room temperature.

[0018] Incidentally, Fe-S compounds with a non-stoichiometric composition in which the composition ratio of Fe and S in FeS deviates by a few percent also have the same crystal structure and magnetic structure as FeS, and maintain the properties as an alternative magnet.

[0019] In FIG. 7, as another example of an alternative magnet, the crystal structure of MnPtAl and the anti-parallel spin arrangement of Mn are shown. MnPtAl has a crystal structure of the regular Ni ２ In structure, and the space group is P6 ３ / mmc, and the Wyckoff position of the Mn ion is 2a. The regular Ni ２ In structure is obtained by filling a metal in the NiAs structure. For example, MnPtAl can be obtained by replacing Fe with Mn, replacing S with Al, and newly filling Pt in FeS with the NiAs structure.

[0020] MnPtAl is an antiferromagnetic metal with a magnetic ordering temperature of 294 K. In FIG. 8A, the measurement results of the magnetic field dependence of the magnetization M and the Hall conductivity σ ｘｙ of MnPtAl at various temperatures (10 K, 50 K, 100 K, 200 K, 270 K, 300 K) are shown. Here, the magnetic field is applied parallel to the

[001] axis. The graph of σ ｘｙ at 200 K shows a value 10 times the actual σ ｘｙ value, and the graphs of σ ｘｙ at 270 K and 300 K show values 20 times the actual σ ｘｙ value. In FIG. 8B, the temperature dependence of the magnetization M of MnPtAl in a zero magnetic field is shown.Here, field cooling was performed under a magnetic field of 0.5 T. From FIGS. 8A and 8B, it can be seen that up to 294 K, the spin arrangement of MnPtAl is maintained, and the spontaneous Hall effect is observed in a zero magnetic field. This means that the ↑↓ state and the ↓↑ state can be electrically distinguished and read out near room temperature.

[0021] Furthermore, Mn-Pt-Al compounds with a non-stoichiometric composition in which the Mn, Pt, and Al composition ratios of MnPtAl differ by a few percent also have the same crystal and magnetic structure as MnPtAl, and maintain their properties as alter magnets.

[0022] The crystal structure of the alter magnet in this embodiment is the NiAs structure, the Troilite structure, and the ordered Ni described above. ２ The structure is not limited to In. As shown in Figure 9, structures with added atoms to the NiAs structure, as well as modified structures, also possess altermagnet properties. In Figure 9, A, B, and C are different atoms, and the white and black symbols indicate the atomic sites at y = 1 / 4 and 3 / 4, respectively, in the NiAs structure. The shift in atomic positions from the parent structure is indicated by arrows. The crystal structure shown in Figure 9 is based on the description in the following literature: Kazuaki Fukamichi, The Magnetics Society of Japan (ed.), "Antiferromagnets - Developments for Applications," Magnetics Library 3, Kyoritsu Shuppan, July 25, 2014, p. 187.

[0023] As shown in Table 1, the alter magnet of this embodiment has a crystal structure defined by a combination of space group and Wyckoff position of magnetic ions, P6 ３ It is one of the following: / mmc and 2a, P-62c and 12i, or Pnma and 4c.

[0024] As described above, the alter magnet of this embodiment is a magnetic material that exhibits an antiparallel spin arrangement with a special crystal structure (see Figure 9 and Table 1) and has a magnetic order in which time-reversal symmetry is broken. Due to these characteristics, there is no leakage magnetic field, enabling high integration of magnetic memory elements. In addition, the response to external fields is two to three orders of magnitude faster than that of ferromagnetic materials, and resistance to magnetic disturbances is increased.

[0025] Next, referring to FIGS. 10 to 15, Examples 1 to 4 of the magnetic memory element using the alter magnet of the present embodiment will be described. In Example 1, a magnetic memory element having a Hall bar structure is targeted (see FIG. 10). In Example 2, a magnetic memory element of a magnetic random access memory (MRAM) using spin-orbit torque (SOT) is targeted (see FIG. 11). In Example 3, a magnetic memory element of MRAM using spin-transfer torque (STT) is targeted (see FIG. 12). In Example 4, a magnetic memory element that optically reads the spin state of the alter magnet is targeted (FIGS. 13 to 15).

[0026] FIG. 10 shows the configuration of a magnetic memory element 100 according to Example 1. The magnetic memory element 100 includes a substrate 10, a spin hall layer 12 laminated on the substrate 10, and an alter magnet layer 14 in contact with the spin hall layer 12.

[0027] The substrate 10 is made of an insulator such as MgO or SiO ２ The spin hall layer 12 is made of a material exhibiting the spin hall effect (hereinafter, spin hall material), for example, a non-magnetic heavy metal such as tantalum (Ta), tungsten (W), platinum (Pt), or a chalcogenide substance such as a topological insulator. The alter magnet layer 14 is made of the alter magnet described above.

[0028] At both ends of the magnetic memory element 100 in the longitudinal direction (x direction), electrodes 16a and 16b are arranged, and electrodes 18a and 18b are arranged in the short direction (y direction). For example, the electrodes 16a and 16b and the electrodes 18a and 18b are made of Au / Ti.

[0029] When writing data to the magnetic memory element 100, a write current I write (pulse current) is passed in the x direction through the spin hall layer 12 between the electrodes 16a and 16b). As a result, a spin current is generated in the plane normal direction (z direction) by the spin hall effect, and the spin-orbit torque acts on the magnetic order of the alter magnet layer 14, causing the magnetic order to reverse. At this time, by applying a weak bias magnetic field in the x direction, the magnetic order of the alter magnet layer 14 is affected by the bias magnetic field, and the rotation direction of the magnetic order is determined.

[0030] In this way, data ("0" or "1") can be written into the alter magnet layer 14. The direction of the write current I write can control the direction of the magnetic order of the alter magnet layer 14. For example, when the write current I write in the +x direction is applied, the magnetic order reverses from the "1" state to the "0" state, and when the write current I write in the -x direction is applied, the magnetic order reverses from the "0" state to the "1" state.

[0031] When reading the data stored in the alter magnet layer 14, a read current I read (DC) is applied in the x direction to the alter magnet layer 14 between the electrodes 16a and 16b. As a result, a Hall voltage V Ｈ is detected between the electrodes 18a and 18b due to the spontaneous Hall effect. The sign of the Hall voltage V Ｈ is determined by the magnetic order of the alter magnet layer 14. For example, when the magnetic order of the alter magnet layer 14 is in the ↑↓ state, it corresponds to the "0" state, and when it is in the ↓↑ state, it corresponds to the "1" state.

[0032] Instead of the magnetic memory element 100 shown in FIG. 10, a configuration in which the spin Hall layer 12 is laminated on the alter magnet layer 14 (substrate / alter magnet layer / spin Hall layer) may be adopted. Also, the alter magnet layer 14 may be sandwiched vertically between two spin Hall layers made of spin Hall materials having different spin Hall angles.

[0033] FIG. 11 shows the configuration of the magnetic memory element 200 of the SOT-MRAM according to Example 2. The magnetic memory element 200 includes a magnetoresistive element 210, a spin Hall layer 220, a first terminal 231, a second terminal 232, a third terminal 233, and transistors Tr1 and Tr2.

[0034] The spin Hall layer 220 is made of a spin Hall material, similar to the spin Hall layer 12 in Figure 10. The magnetoresistive element 210 comprises a free layer 212, which is an alter magnet layer in contact with the spin Hall layer 220 and in which the magnetic order can be reversed; a non-magnetic layer 214 laminated on the free layer 212; and a reference layer 216 laminated on the non-magnetic layer 214, in which the magnetic order is fixed. In Figure 11, an example is shown where the magnetic order of the free layer 212 and the reference layer 216 is oriented perpendicular to the plane, but it may also be oriented in the in-plane direction.

[0035] The free layer 212 consists of an alter magnet similar to the alter magnet layer 14 in Figure 10. The non-magnetic layer 214 is an insulator (for example, MgO, AlOx, or MgAl ２ O ４ The magnetoresistive element 210 consists of the following. The reference layer 216 is made of a ferromagnetic material (for example, CoFeB). The reference layer 216 may be made of the same alter magnet as the free layer 212, in which case the alter magnet of the reference layer 216 has a greater coercivity than the alter magnet of the free layer 212. The magnetoresistive element 210 functions as a magnetic tunnel junction (MTJ) element.

[0036] The magnetoresistive element 210 is assigned a single bit of data, either "0" or "1", depending on its resistance state. For example, when the reference layer 216 and the free layer 212 are made of the same alter magnet and the magnetic order is in the same direction (for example, both layers are in an ↑↓ state), the magnetoresistive element 210 is in a low resistance state. When the magnetic order is in opposite directions (for example, the reference layer 216 is in an ↑↓ state and the free layer 212 is in a ↓↑ state), the magnetoresistive element 210 is in a high resistance state. For example, the data for the low resistance state can be assigned as "0", and the data for the high resistance state can be assigned as "1".

[0037] The first terminal 231, the second terminal 232, and the third terminal 233 are made of metal. The first terminal 231 is connected to the reference layer 216, the second terminal 232 is connected to one end of the spin Hall layer 220, and the third terminal 233 is connected to the other end of the spin Hall layer 220. The first terminal 231 is connected to the ground line 240. The ground line 240 is set to the ground voltage. However, the ground line 240 may be set to a reference voltage other than the ground voltage.

[0038] Transistors Tr1 and Tr2 are, for example, N-channel metal oxide semiconductor (NMOS) transistors. The second terminal 232 is connected to the drain of transistor Tr1, and the third terminal 233 is connected to the drain of transistor Tr2. The gates of transistors Tr1 and Tr2 are connected to the word line WL. The source of transistor Tr1 is connected to the first bit line BL1, and the source of transistor Tr2 is connected to the second bit line BL2.

[0039] As shown in Figure 11, when the magnetic order of the free layer 212 and the reference layer 216 is oriented perpendicular to the plane, the writing current I is when writing data to the magnetoresistive element 210. write A weak bias magnetic field is applied in the direction, the word line WL is set to a high level to turn on transistors Tr1 and Tr2, and one of the first bit line BL1 and the second bit line BL2 is set to a high level and the other to a low level. As a result, a write current I is generated in the in-plane direction of the spin Hall layer 220 between the first bit line BL1 and the second bit line BL2. write The flow of current generates a spin current perpendicular to the plane, and the magnetic order of the free layer 212 is reversed by SOT, allowing data to be written. Writing current I write The data written can be changed depending on the orientation of the device.

[0040] When reading data stored in the magnetoresistive element 210, the word line WL is set to high level to turn on transistors Tr1 and Tr2, one bit line (second bit line BL2) is set to high level, and the other bit line (first bit line BL1) is left open. As a result, a read current I is drawn from the high-level second bit line BL2 to the third terminal 233, spin Hall layer 220, free layer 212, non-magnetic layer 214, reference layer 216, first terminal 231, and ground line 240. read A current flows. Due to the magnetoresistive effect, the readout current I read By measuring its size, the resistance state of the magnetoresistive element 210, that is, the stored data, can be determined.

[0041] Figure 12 shows the configuration of the magnetic memory element 300 of the STT-MRAM according to Embodiment 3. The magnetic memory element 300 comprises a magnetoresistive element 310, a first terminal 321, a second terminal 322, and a transistor Tr.

[0042] The magnetoresistive element 310 comprises a reference layer 316 with a fixed magnetic order, a non-magnetic layer 314 laminated on the reference layer 316, and a free layer 312, which is an alter-magnet layer laminated on the non-magnetic layer 314 and whose magnetic order can be reversed. The free layer 312, the non-magnetic layer 314, and the reference layer 316 are made of the same materials as the free layer 212, the non-magnetic layer 214, and the reference layer 216 in Figure 11, respectively.

[0043] Note that Figure 12 shows an example where the magnetic order of the free layer 312 and the reference layer 316 is oriented perpendicular to the plane, but it may also be oriented in the in-plane direction. Similar to the magnetoresistive element 210 in Figure 11, the magnetoresistive element 310 is assigned one bit of data, either "0" or "1", depending on its resistance state.

[0044] The first terminal 321 and the second terminal 322 are made of metal. The free layer 312 is connected to the first terminal 321, and the reference layer 316 is connected to the second terminal 322. The first terminal 321 is connected to the bit line BL, and the second terminal 322 is connected to the transistor Tr.

[0045] The transistor Tr is, for example, an NMOS transistor. The drain of transistor Tr is connected to the second terminal 322, the source line SL is connected to the source, and the gate is connected to the word line WL.

[0046] When writing data to the magnetoresistive element 310, the word line WL is set to a high level to turn on the transistor Tr, and a writing current I perpendicular to the plane is applied between the bit line BL and the source line SL. write The current is passed through. This reverses the magnetic order of the free layer 312 by the STT, allowing data to be written. Writing current I write The data written can be changed depending on the orientation of the device.

[0047] When reading data stored in the magnetoresistive element 310, the word line WL is set to a high level to turn on the transistor Tr, and a read current I is passed between the bit line BL and the source line SL. read A current flows through it. Due to the magnetoresistive effect, the readout current I read By measuring its size, the resistance state of the magnetoresistive element 310, that is, the stored data, can be determined.

[0048] In Examples 2 (Figure 11) and 3 (Figure 12), the magnetoresistive elements 210 and 310 are shown as MTJ elements, but they can also function as giant magnetoresistance (GMR) elements. In this case, the non-magnetic layers 214 and 314 are made of non-magnetic metal (conductor).

[0049] By utilizing magneto-optical effects such as X-ray magnetic circular dichroism (XMCD) and the Kerr effect, it should be possible to optically read out the spin state of an alternator magnet. As shown in Figure 13, XMCD is a phenomenon in which the transmittance (or absorption spectrum) differs depending on whether the sample is irradiated with right-circularly polarized X-rays or left-circularly polarized X-rays, due to the spin order of the sample.

[0050] XMCD experiments use the total electron yield method, which measures the total amount of electrons emitted when a material is irradiated with X-rays. Specifically, when a sample is irradiated with circularly polarized X-rays, a current proportional to the absorbed X-rays flows through the sample. By measuring this current, an X-ray absorption spectrum can be obtained. In Example 4, to measure the XMCD of a bulk single crystal of FeS, the FeS sample is irradiated with soft X-rays in the L-edge region at room temperature.

[0051] Figure 14 shows the XMCD measurement results for bulk single crystal FeS at room temperature. Specifically, the upper part of Figure 14 shows the average value (XAS signal) of two X-ray absorption spectra measured with right-circular polarization and left-circular polarization, while the lower part of Figure 14 shows the difference spectrum (XMCD signal) of two X-ray absorption spectra measured with right-circular polarization and left-circular polarization.

[0052] Figure 15 shows the magnetic field dependence of the readout signal (XMCD signal) when an FeS sample is irradiated with 706.55 eV X-rays. From Figure 15, the signs of the readout signals are reversed because the direction of the virtual magnetic field is opposite for the ↑↓ state ("0") and the ↓↑ state ("1"). In this way, two spin states can be optically read out at room temperature through the XMCD caused by antiparallel spin order. Furthermore, X-ray readout enables magnetic imaging with spatial resolution on the order of nanometers.

[0053] Furthermore, X-ray reading of the spin state can be expected for alter magnets other than FeS (see Figure 9). Additionally, spin state reading using visible light is also expected using the Kerr effect. Reading with visible light enables magnetic imaging with a spatial resolution on the order of micrometers.

[0054] Thus, the spin state of the alternator magnet in this embodiment can be detected not only electrically (Examples 1-3) but also optically (Example 4).

[0055] In Example 1 (Figure 10), a magnetic memory device equipped with a plurality of magnetic memory elements 100 may be provided. Also, in Example 2 (Figure 11), a magnetic memory device in which a plurality of magnetic memory elements 200 are arranged in a matrix may be provided. Similarly, in Example 3 (Figure 12), a magnetic memory device in which a plurality of magnetic memory elements 300 are arranged in a matrix may be provided. Similarly, a magnetic memory device in which the magnetic memory elements according to Example 4 are arranged in a matrix may be provided.

[0056] The present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention.

[0057] 10 Substrate 14 Alter Magnet Layer 12, 220 Spin Hall Layer 100, 200, 300 Magnetic Memory Element 210, 310 Magnetoresistive Element 212, 312 Free Layer 214, 314 Non-magnetic Layer 216, 316 Reference Layer

Claims

1. The crystal structure defined by the combination of the space group and the Wyckoff position of the magnetic ion is P6 ３ A magnetic memory element comprising an alter magnet layer made of a magnetic material having a magnetic order in which time-reversal symmetry is broken, wherein the magnetic ions exhibit an antiparallel spin arrangement and one of the following: / mmc and 2a, P-62c and 12i, and Pnm and 4c.

2. The crystal structure of the magnetic material is a NiAs structure, a troilite structure, and Ni ２ A magnetic memory element according to claim 1, which is any one of the In structures.

3. The magnetic memory element according to claim 2, wherein the magnetic material is FeS with a NiAs structure or an Fe-S compound with a non-stoichiometric composition.

4. The magnetic memory element according to claim 2, wherein the magnetic material is FeS with a troilite structure or an Fe-S compound with a non-stoichiometric composition.

5. The magnetic material follows the order Ni ２ The magnetic memory element according to claim 2, wherein the element is MnPtAl with an In structure or a Mn-Pt-Al compound with a non-stoichiometric composition.

6. A magnetic memory element according to claim 1, comprising a spin Hall layer that contacts the alter magnet layer and is made of a material that exhibits the spin Hall effect, wherein a spin current is generated in the perpendicular direction when a writing current flows in the in-plane direction, and wherein the alter magnet layer is capable of reversing its magnetic order by the spin orbit torque generated by the spin current acting on the magnetic order of the magnetic material.

7. The magnetic memory element according to claim 6, wherein a spontaneous Hall effect is generated in the alter magnet layer by a virtual magnetic field originating from the quantum phase, and data stored in the alter magnet layer is read out using the spontaneous Hall effect.

8. A magnetic memory element according to claim 1, comprising: a spin Hall layer made of a material exhibiting the spin Hall effect, wherein a spin current is generated perpendicular to the plane when a writing current flows in the in-plane direction; a free layer which is an alternator magnet layer in contact with the spin Hall layer, and on which the magnetic order can be reversed by the spin orbit torque generated by the spin current acting on the magnetic order of the magnetic material; a reference layer on which the magnetic order is fixed; and a non-magnetic layer provided between the free layer and the reference layer.

9. A magnetic memory element according to claim 1, comprising: a reference layer in which the magnetic order is fixed; a free layer which is an alter magnet layer in which the magnetic order of the magnetic material can be reversed by spin transfer torque when a writing current flows in the direction perpendicular to the plane; and a non-magnetic layer provided between the reference layer and the free layer.

10. A magnetic memory device comprising a plurality of magnetic memory elements, wherein each of the plurality of magnetic memory elements is defined as the magnetic memory element described in claim 6.

11. A magnetic memory device comprising a plurality of magnetic memory elements, wherein each of the plurality of magnetic memory elements is defined as the magnetic memory element described in claim 8.

12. A magnetic memory device comprising a plurality of magnetic memory elements, wherein each of the plurality of magnetic memory elements is defined as the magnetic memory element described in claim 9.

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