Magnetic head with assisted magnetic recording and method of making thereof

1. A magnetic head, comprising:

a main pole configured to serve as a first electrode;

an upper pole comprising a trailing magnetic shield configured to a serve as a second electrode; and

an electrically conductive portion comprising a multilayer stack located in a trailing gap between the main pole and the trailing magnetic shield;

wherein the electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion comprises at least one first layer comprising an electrically conductive, non-magnetic material and at least one second layer comprising a material different than the at least one first layer, wherein the electrically conductive, non-magnetic material portion is recessed from an air bearing surface (ABS); and

wherein the main pole and the trailing magnetic shield are electrically shorted by the at least one first layer of the electrically conductive portion across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the at least one second layer of the electrically conductive portion.

2. The magnetic head of claim 1 , further comprising:

an electrical bias circuitry configured to flow electrical current between the first electrode and the second electrode through the electrically conductive portion;

a first electrical contact connecting a portion of the main pole distant from an air bearing surface to the electrical bias circuitry;

a second electrical contact connecting a portion of the upper pole distant from the air bearing surface to the electrical bias circuitry; and

an electrically insulating material layer located between the portions of the main pole and the upper pole distal from the air bearing surface.

3. The magnetic head of claim 2 , wherein:

the electrically insulating material layer provides physical and electrical isolation between the portions of the main pole and the upper pole distal from the air bearing surface; and

the only electrically conductive path between the main pole and the upper pole is the electrically conductive path between the main pole and the trailing magnetic shield through the at least one second layer of the electrically conductive portion.

4. The magnetic head of claim 1 , wherein:

the magnetic head comprises a head which lacks a spin torque oscillator stack; and

the air bearing surface (ABS) of the magnetic head includes planar surfaces of the main pole, the electrically conductive portion, and the trailing magnetic shield.

5. The magnetic head of claim 4 , wherein the electrically conductive portion contacts a trailing sidewall of the main pole and a leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

6. The magnetic head of claim 1 , wherein the electrically conductive portion contacts a trailing sidewall of the main pole and a leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

7. The magnetic head of claim 5 , wherein the at least one first layer of the electrically conductive portion comprises a copper, gold, platinum, ruthenium, chromium or tungsten layer which contacts the trailing sidewall of the main pole and the leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

8. The magnetic head of claim 1 , wherein the at least one second layer of the electrically conductive portion comprises an electrically conductive, magnetic layer, wherein the electrically conductive portion contacts a trailing sidewall of the main pole and a leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

9. The magnetic head of claim 1 , further comprising an electrical coil that is located adjacent to the main pole and configured to generate a magnetic flux through the main pole upon conduction of electrical current through the electrical coil.

10. A hard disk drive, comprising:

the magnetic head of claim 9 ;

a slider supporting the magnetic head;

an actuator arm supporting the slider;

a voice coil motor configured to control the actuator arm; and

a magnetic disk.

11. A method of operating a magnetic recording head comprising providing a current between a main pole and an upper pole containing a trailing magnetic shield through an electrically conductive portion located in a trailing gap between the main pole and the trailing magnetic shield while applying a magnetic field to the main pole from a coil to record data to a magnetic disk,

wherein the electrically conductive portion is not part of a spin torque oscillator stack, and the electrically conductive portion comprises at least one electrically conductive, non-magnetic material layer, wherein the electrically conductive, non-magnetic material portion is recessed from an air-bearing surface (ABS).

12. The method of claim 11 , wherein:

the current is provided through a first electrical contact connecting a portion of the main pole distant from the air bearing surface to electrical bias circuitry and a second electrical contact connecting a portion of the upper pole distant from the air bearing surface to the electrical bias circuitry;

an electrically insulating material layer is located between the portions of the main pole and the upper pole distal from the air bearing surface;

the electrically insulating material layer provides physical and electrical isolation between the portions of the main pole and the upper pole distal from the air bearing surface; and

the current flows between the main pole and the upper pole only through the electrically conductive portion.

13. The method of claim 11 , wherein:

the magnetic recording head comprises a head which lacks a spin torque oscillator stack;

the air bearing surface (ABS) of the magnetic recording head includes planar surfaces of the main pole, the electrically conductive portion, and the trailing magnetic shield; and

the current flows through an electrically conductive path which is present between the main pole and the upper pole through the electrically conductive portion which contacts the main pole and the trailing magnetic shield.

14. The method claim 11 , wherein the electrically conductive portion contacts a trailing sidewall of the main pole and a leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

15. The method of claim 14 , wherein:

the electrically conductive portion comprises a single electrically conductive, non-magnetic material layer, a multilayer stack of electrically conductive, non-magnetic layers, or a multilayer stack of electrically conductive, magnetic and non-magnetic layers; and

the electrically conductive portion contacts the trailing sidewall of the main pole and the leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.

16. The method of claim 14 , wherein the electrically conductive portion comprises a copper gold, platinum, ruthenium, chromium or tungsten layer which contacts the trailing sidewall of the main pole and the leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.