Magnetic head assembly
A magnetic head assembly includes: a magnetic recording head, a head slider, a suspension and an actuator arm. The magnetic recording head includes a spin torque oscillator and a main magnetic pole. The spin torque oscillator includes, a first magnetic layer including at least one selected from the group consisting of a Fe—Co—Al alloy, a Fe—Co—Si alloy, a Fe—Co—Ge alloy, a Fe—Co—Mn alloy a Fe—Co—Cr alloy and a Fe—Co—B alloy, a second magnetic layer, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The main magnetic pole is placed together with the spin torque oscillator. The magnetic recording head is mounted on the head slider. The head slider is mounted on one end of the suspension. The actuator arm is connected to other end of the suspension.
1. A magnetic recording apparatus comprising:
a magnetic head assembly including:
a magnetic recording head including:
a spin torque oscillator including:
an oscillation layer including a Fe—Co alloy containing at least one selected from the group consisting of Al, Si, Ge, Mn, Cr, and B, the Fe—Co alloy having bcc structure, and an Fe composition of the Fe—Co alloy being 20 atomic % or more, the oscillation layer having a thickness from 5-20 nanometers and a saturation magnetization from 500-1300 emu/cc,
a spin injection layer including a magnetic film with an anisotropy perpendicular to a film surface of the magnetic film, and
an intermediate layer provided between the oscillation layer and the spin injection layer; and
a main magnetic pole placed together with the spin torque oscillator;
a head slider, the magnetic recording head being mounted on the head slider;
a suspension, the head slider being mounted on a first end of the suspension; and
an actuator arm connected to a second end of the suspension;
a magnetic recording medium; and
a signal processor configured to write and read a signal on the magnetic recording medium using the magnetic recording head.
2. The apparatus according to claim 1 , wherein a coercitivity of the oscillation layer is lower than a magnetic field applied from the main magnetic pole, and a coercitivity of the spin injection layer is lower than a magnetic field applied from the main magnetic pole.
3. The apparatus according to claim 1 , wherein the oscillation layer is disposed between the main magnetic pole and the spin injection layer.
4. The apparatus according to claim 1 , wherein the spin injection layer is disposed between the main magnetic pole and the oscillation layer.
5. The apparatus according to claim 1 , wherein the oscillation layer is a Fe—Co—Al alloy, and an Al composition of the Fe—Co—Al alloy is 12 atomic % or more and 40 atomic % or less.
6. The apparatus according to claim 1 , wherein the spin injection layer includes a Fe—Co—Al alloy at the interface between the spin injection layer and the intermediate layer, and an Al composition of the Fe—Co—Al alloy is 12 atomic % or more and 40 atomic % or less.
7. The apparatus according to claim 1 , wherein the magnetic film includes at least of CoCrPt, CoCrTa, CoCrTaPt, CoCrTaNb and TbFeCo.
8. The apparatus according to claim 1 , wherein the magnetic film includes an artificial lattice portion including at least one of Co/Pd, Co/Pt and CoCrTa/Pd.
9. The apparatus according to claim 1 , wherein the magnetic film includes at least one of a CoCr-based alloy, a RE-TM-based amorphous alloy, a Co artificial lattice, a CoPt-based alloy, a FePt-based alloy and a SmCo-based alloy.