Microwave-assisted magnetic recording head with asymmetric side gap for shingled magnetic recording

摘要

Approaches to improving the signal-to-noise ratio in a microwave-assisted magnetic recording hard disk drive over the entire region from the inner diameter to the outer diameter of the disk, especially in the context of shingled magnetic recording, include a narrower side gap on the side opposing a spin torque oscillator offset direction than the side gap in the offset direction, thereby increasing the gradient of the recording magnetic field in the cross-track direction and reducing the track edge noise of the recording pattern. Embodiments include use of a side shield on the side opposing the offset direction that has a higher saturation magnetization than the side shield on the side in the offset direction, thereby further increasing the gradient of the recording magnetic field in the cross-track direction.

主权项

1. A microwave-assisted magnetic recording (MAMR) head comprising:
a magnetic writer main pole extending to an air bearing surface; a shield wrapping around at least a portion of said main pole, said shield comprising a trailing shield at a trailing side of said main pole and a side shield at each respective side of said main pole in a cross-track direction; a gap between said main pole and said shield, said gap comprising a trailing gap between said trailing shield and said main pole and a side gap between each respective side shield and said main pole; a spin torque oscillator (STO) element positioned between said main pole and said trailing shield and offset in a particular offset direction from a centerline of said main pole; and wherein the side gap positioned on the side opposing said offset direction is narrower than the side gap positioned on the side of said offset direction.