Magnetic head for microwave assisted magnetic recording
Embodiments of the present invention generally relate to a MAMR head. The MAMR head includes an STO and an embedded contact sensor (ECS). The STO and the ECS are electrically connected in series and are connected to the same terminals. During operation, the current applied to the STO is controlled with respect to a change in resistance of the ECS.
1. A microwave assisted magnetic recording head, comprising:
a spin torque oscillator; and
a contact sensor electrically coupled to the spin torque oscillator, wherein a distance between the spin torque oscillator and the contact sensor is greater than a result of a formula: 10 −7 *(R/60)*(2*π*r), wherein R is a disk rotational speed in rotations per minute and r is a levitated radial position of a slider with respect to a disk in millimeters.
2. The microwave assisted magnetic recording head of claim 1 , further including a main pole and a trailing shield, wherein the spin torque oscillator is electrically coupled to the main pole and the trailing shield.
3. The microwave assisted magnetic recording head of claim 2 , wherein the contact sensor is electrically connected to the main pole.
4. The microwave assisted magnetic recording head of claim 3 , wherein the contact sensor is electrically connected to a first terminal.
5. The microwave assisted magnetic recording head of claim 4 , wherein the trailing shield is electrically connected to a second terminal.
6. The microwave assisted magnetic recording head of claim 5 , wherein the contact sensor is electrically connected to the second terminal via the main pole, the spin torque oscillator and the trailing shield.
7. The microwave assisted magnetic recording head of claim 6 , wherein the contact sensor is disposed at a location that is leading to the spin torque oscillator relative to movement of a magnetic recording disk.
8. The microwave assisted magnetic recording head of claim 1 , wherein the contact sensor includes a material selected from the group consisting of Ta, Pt, Au, Rh, NiFe, and alloys thereof.
9. The microwave assisted magnetic recording head of claim 1 , wherein the contact sensor is disposed at a location that is leading to the spin torque oscillator relative to movement of a magnetic recording disk.
10. A microwave assisted magnetic recording head, comprising:
a spin torque oscillator having a first width; and
a contact sensor electrically coupled to the spin torque oscillator, wherein the contact sensor has a second width that is greater than the first width, and wherein the second width is greater than a result of a formula: W1+Tan A1*D+Tan A2*D, wherein W1 is the first width, A1 and A2 are skew angles with respect to the spin torque oscillator and the contact sensor and D is a distance between the spin torque oscillator and the contact sensor.