Spin current magnetization rotational magnetic element, spin current magnetization rotational magnetoresistance effect element, and magnetic memory
A spin current magnetization rotational magnetic element in which magnetization can be rotated without applying an external magnetic field, power saving and a degree of integration can be enhanced. The spin current magnetization rotational magnetic element includes a spin-orbit torque wiring in a first direction; a first ferromagnetic layer in a second direction, a magnetization direction of the first ferromagnetic layer being configured to change; and a spin injection layer which is in contact with a surface of the spin-orbit torque wiring on a side opposite to the first ferromagnetic layer side and laminated in the second direction, in which the magnetization direction of the first ferromagnetic layer is a Z direction and the magnetization direction of the spin injection layer is an X direction in the first direction.
1. A spin current magnetization rotational magnetic element comprising:
a spin-orbit torque wiring extending in a first direction;
a first ferromagnetic layer positioned in a second direction which is a direction intersecting the first direction of the spin-orbit torque wiring, a magnetization direction of the first ferromagnetic layer being configured to change; and
a spin injection layer which is in contact with a surface of the spin-orbit torque wiring on a side opposite to the first ferromagnetic layer side and laminated in the second direction, wherein
the magnetization direction of the first ferromagnetic layer has a Z direction component in the second direction,
a magnetization direction of the spin injection layer has an X direction component in the first direction, and
the spin injection layer is formed of a ferromagnetic material.
2. The spin current magnetization rotational magnetic element according to claim 1 , wherein the spin injection layer is made of; a metal selected from a group consisting of Cr, Mn, Co, Fe, and Ni; an alloy containing one or more metal of Cr, Mn, Co, Fe, and Ni; an alloy containing at least one element selected from a group consisting of Cr, Mn, Co, Fe, and Ni and at least one element selected from a group consisting of B, C, and N; or a ferromagnetic material containing a rare-earth element.
3. The spin current magnetization rotational magnetic element according to any one of claim 1 , wherein the spin injection layer is a ferromagnetic laminate in which at least two ferromagnetic material layers are alternately laminated multiple times.
4. The spin current magnetization rotational magnetic element according to claim 1 , wherein the spin injection layer has a tetragonal crystalline structure and a c-axis length is shorter than an a-axis length in a crystal lattice of the tetragonal crystalline structure.
5. The spin current magnetization rotational magnetic element according to claim 1 , wherein a film thickness of the spin-orbit torque wiring is equal to or less than a spin diffusion length of the spin-orbit torque wiring.
6. The spin current magnetization rotational magnetic element according to claim 1 , wherein a length in the first direction of the spin injection layer is equal to or greater than a length in the first direction of the spin-orbit torque wiring.
7. A spin current magnetization rotational magnetoresistance effect element comprising:
the spin current magnetization rotational magnetic element according to claim 1 ; and
a nonmagnetic layer and a second ferromagnetic layer disposed in this order on a surface of the first ferromagnetic layer on a side opposite to the spin-orbit torque wiring.
8. A magnetic memory comprising a plurality of spin current magnetization rotational magnetoresistance effect elements according to claim 7 .
9. A spin current magnetization rotational magnetic element comprising:
a spin-orbit torque wiring extending in a first direction;
a first ferromagnetic layer positioned in a second direction which is a direction intersecting the first direction of the spin-orbit torque wiring, a magnetization direction of the first ferromagnetic layer being configured to change; and
a spin injection layer which is in contact with a surface of the spin-orbit torque wiring on a side opposite to the first ferromagnetic layer side and laminated in the second direction, wherein
the magnetization direction of the first ferromagnetic layer is an X direction in the first direction,
the magnetization direction of the spin injection layer is a Z direction in the second direction, and
the spin injection layer is formed of a ferromagnetic material.
10. The spin current magnetization rotational magnetic element according to claim 9 , wherein the spin injection layer is made of; a metal selected from a group consisting of Cr, Mn, Co, Fe, and Ni; an alloy containing one or more metal of Cr, Mn, Co, Fe, and Ni; an alloy containing at least one element selected from a group consisting of Cr, Mn, Co, Fe, and Ni and at least one element selected from a group consisting of B, C, and N; or a ferromagnetic material containing a rare-earth element.
11. The spin current magnetization rotational magnetic element according to claim 9 , wherein the spin injection layer is a ferromagnetic laminate in which at least two ferromagnetic material layers are alternately laminated multiple times.
12. The spin current magnetization rotational magnetic element according to claim 9 , wherein the spin injection layer has a tetragonal crystalline structure and a c-axis length is shorter than an a-axis length in a crystal lattice of the tetragonal crystalline structure.
13. The spin current magnetization rotational magnetic element according to claim 9 , wherein a film thickness of the spin-orbit torque wiring is equal to or less than a spin diffusion length of the spin-orbit torque wiring.
14. The spin current magnetization rotational magnetic element according to claim 9 , wherein a length in the first direction of the spin injection layer is equal to or greater than a length in the first direction of the spin-orbit torque wiring.
15. A spin current magnetization rotational magnetoresistance effect element comprising:
the spin current magnetization rotational magnetic element according to claim 9 ; and
a nonmagnetic layer and a second ferromagnetic layer disposed in this order on a surface of the first ferromagnetic layer on a side opposite to the spin-orbit torque wiring.
16. A magnetic memory comprising a plurality of spin current magnetization rotational magnetoresistance effect elements according to claim 15 .