Spin current generator for STT-MRAM or other spintronics applications
View Patent ↗Spin current generators and systems and methods for employing spin current generators. A spin current generator may be configured to generate a spin current polarized in one direction, or a spin current selectively polarized in two directions. The spin current generator may by employed in spintronics applications, wherein a spin current is desired.
1. A device comprising:
a spin-polarizing layer configured to polarize a programming current such that the programming current is polarized in a first direction; and
a non-magnetic layer disposed directly on a first surface of the spin-polarizing layer; and
a heater material formed adjacent to the spin-polarizing layer and the nonmagnetic layer.
2. The device, as set forth in claim 1 , comprising an insulative material adjacent to the spin-polarizing layer and non-magnetic layer.
3. The device, as set forth in claim 1 , comprising a piezoelectric material adjacent to the spin-polarizing layer and non-magnetic layer.
4. The device, as set forth in claim 3 , wherein the device is configured to produce polarized current of various polarization degrees through a transient stress effect induced by the piezoelectric material.
5. The device, as set forth in claim 1 , comprising an antiferromagnetic layer disposed directly on a second surface of the spin-polarizing layer.
6. The device, as set forth in claim 1 , wherein the spin-polarizing layer comprises a ferromagnetic material.
7. The device, as set forth in claim 1 , wherein the heater material is configured to apply heat to decrease or eliminate the magnetization or spin polarization of the spin-polarizing layer.
8. The device, as set forth in claim 1 , comprising a transistor coupled to the device wherein current flows through and controls the polarity of the current that is output by the device.
9. The device, as set forth in claim 1 , wherein the device is configured to generate a unidirectional spin current polarized in either direction.
10. A device comprising:
a spin-polarizing layer configured to polarize a programming current such that the programming current is polarized in a first direction; and
a non-magnetic layer disposed directly on a first surface of the spin-polarizing layer; and
a piezoelectric stress material formed adjacent to the spin-polarizing layer and the non-magnetic layer.
11. The device, as set forth in claim 10 , comprising a heater material formed adjacent to the spin-polarizing layer and the nonmagnetic layer.
12. The device, as set forth in claim 10 , comprising an antiferromagnetic layer disposed directly on a second surface of the spin-polarizing layer.
13. The device, as set forth in claim 10 , wherein the spin-polarizing layer comprises a ferromagnetic material.
14. The device, as set forth in claim 10 , wherein the device is configured to produce polarized current of various polarization degrees through a transient stress effect induced by the piezoelectric stress material.
15. The device, as set forth in claim 10 , comprising a transistor coupled to the device wherein current flows through and controls the polarity of the current that is output by the device.
16. The device, as set forth in claim 10 , wherein the device is configured to generate a unidirectional spin current polarized in either direction.
17. A device comprising:
an array of memory cells;
a structure configured to generate a unidirectional spin current to the array of memory cells; and
wherein the structure is configured to generate a unidirectional non-spin polarized current and the structure comprises a spin-polarizing layer and a heater material that decreases or eliminates a spin polarization of the spin-polarizing layer.
18. The device, as set forth in claim 17 , wherein each of the memory cells in the array of memory cells are coupled to each other and the structure by source lines, and the structure is configured to send a current through the source line to each of the memory cells.
19. The device, as set forth in claim 17 , wherein each of the memory cells in the array of memory cells comprises a spin torque transfer magnetic random access memory cell having a pinned layer configured to a fixed magnetization in one direction and a free layer configured to be magnetized in either direction.
20. The device, as set forth in claim 19 , wherein the pinned and free layers comprise ferromagnetic materials.
21. The device, as set forth in claim 19 , comprising an antiferromagnetic material deposited below the pinned layer.
22. The device, as set forth in claim 19 , comprising a nonmagnetic layer deposited between the free layer and the pinned layer.
23. The device, as set forth in claim 19 , wherein the device is configured to output a current with a polarity in one direction to set the magnetization of the free layer to that direction and program the memory cell in a first state, and to output a current with a polarity in a different direction to set the magnetization of the free layer to that direction and program the memory cell in a second state.