Microwave assisted magnetic recording head having spin torque oscillator, and magnetic recording apparatus
A spin torque oscillator generates a strong high-frequency magnetic field stably and has high reliability. A magnetic recording head includes a main magnetic pole and a spin torque oscillator. A magnetization control layer is antiferromagnetically coupled via a non-magnetic coupling layer with an interface contacting a high-frequency magnetic field generation layer of the spin torque oscillator.
1. A microwave assisted magnetic recording head comprising:
a main magnetic pole; and
a spin torque oscillator,
wherein the spin torque oscillator includes a high-frequency magnetic field generation layer antiferromagnetically coupled with a magnetization control layer via a non-magnetic coupling layer;
wherein the spin torque oscillator having a multilayer film structure is stacked on the main magnetic pole in a film thickness direction,
wherein the spin torque oscillator includes an underlayer, a spin injection layer, a spin conduction layer, the high-frequency magnetic field generation layer, the non-magnetic coupling layer, the magnetization control layer, and a capping layer which are stacked on the main magnetic pole in the recited order.
2. The microwave assisted magnetic recording head according to claim 1 , wherein the magnetization control layer is a perpendicular magnetic anisotropy film with a magnetic easy axis in a direction perpendicular to a film plane.
3. The microwave assisted magnetic recording head according to claim 1 , wherein the non-magnetic coupling layer includes at least one material selected from Ru and Ru—Fe.
4. The microwave assisted magnetic recording head according to claim 1 , wherein the magnetization control layer is a multilayer film of Co and Ni.
5. A microwave assisted magnetic recording head comprising:
a main magnetic pole; and
a spin torque oscillator,
wherein the spin torque oscillator includes a high-frequency magnetic field generation layer antiferromagnetically coupled with a magnetization control layer via a non-magnetic coupling layer;
wherein the spin torque oscillator having a multilayer film structure is stacked on the main magnetic pole in a film thickness direction,
wherein the spin torque oscillator includes an underlayer, the magnetization control layer, the non-magnetic coupling layer, the high-frequency magnetic field generation layer, a spin conduction layer, a spin injection layer, and a capping layer which are stacked on the main magnetic pole in the recited order.
6. The microwave assisted magnetic recording head according to claim 5 , wherein the magnetization control layer is a perpendicular magnetic anisotropy film with a magnetic easy axis in a direction perpendicular to a film plane.
7. The microwave assisted magnetic recording head according to claim 5 , wherein the non-magnetic coupling layer includes at least one material selected from Ru and Ru—Fe.
8. The microwave assisted magnetic recording head according to claim 5 , wherein the magnetization control layer is a multilayer film of Co and Ni.