Perpendicular magnetic recording system and write head with transverse auxiliary pole for fast switching of write pole magnetization
View Patent ↗A perpendicular magnetic recording system has a write head having a main coil (the write coil) and main pole (the write pole) that directs write flux in a direction perpendicular to the recording layer in the magnetic recording medium, and a transverse auxiliary pole (TAP) that injects auxiliary magnetic flux into the write pole at an angle to the primary or perpendicular axis of the write pole. The additional flux from the TAP, which is injected non-parallel to the primary magnetization of the write pole, exerts a torque on the magnetization of the write pole, thereby facilitating magnetization reversal of the write pole. The TAP is coupled to the main coil but not electrically connected to it. A separate passive coil, not electrically connected to the main coil, may be wrapped as a loop around the main pole and the TAP. Alternatively, the TAP may be located near one of the electrically conductive turns of the main coil.
1. A perpendicular magnetic recording write system for magnetizing regions in a perpendicular magnetic recording layer comprising:
a write head comprising
a main pole;
a main electrically conductive coil around the main pole for generating magnetic flux in the main pole;
a transverse auxiliary pole (TAP) coupled to the main coil and oriented at an angle to the main pole greater than 15 degrees and less than or equal to 90 degrees; and
a write driver capable of supplying write current to the main coil, the TAP directing magnetic flux to the main pole in response to the write current.
2. The system of claim 1 wherein the TAP is oriented substantially orthogonal to the main pole.
3. The system of claim 1 further comprising an auxiliary coil around the main pole and the TAP, the auxiliary coil not being electrically connected to the main coil.
4. The system of claim 1 wherein the main coil has multiple turns and wherein the TAP is located near one of the turns of the main coil.
5. The system of claim 1 wherein the main coil is a pancake coil.
6. The system of claim 1 wherein the main coil is a helical coil.
7. A magnetic recording disk drive perpendicular recording write head for magnetizing regions in data tracks of a perpendicular magnetic recording layer on the disk, the write head being formed on a slider having an air-bearing surface (ABS) facing the recording layer and comprising:
a substrate;
a main pole on the substrate;
a write pole on the main pole and having an end substantially at the ABS;
a main electrically conductive coil around the main pole for generating magnetic flux in the main pole and its connected write pole; and
a transverse auxiliary pole (TAP) magnetically coupled to the main coil and oriented substantially orthogonal to the write pole.
8. The write head of claim 7 further comprising an auxiliary coil around the main pole and the TAP, the auxiliary coil not being electrically connected to the main coil.
9. The write head of claim 7 wherein the main coil has multiple turns and wherein the TAP is located near the turn closest to the ABS.
10. The write head of claim 7 wherein the main coil is a pancake coil.
11. The write head of claim 7 wherein the main coil is a helical coil.
12. A magnetic recording disk drive perpendicular recording write system comprising:
the write head of claim 7 ; and
a write driver for supplying write current to the main coil, whereby the TAP generates magnetic flux substantially orthogonal to the write pole in response to write current from the write driver.