High frequency magnetization response observed at the air-bearing surfaces of thin film heads

Abstract

Magnetization response during high frequency and high amplitude write current excitations at the air-bearing surfaces (ABS) of thin film inductive and MR write heads were observed by using a Scanning Kerr Effect Microscope. Under certain excitation conditions, bubble-like dynamic domain walls that separate the regions of 180' out-of-phase magnetization reversals were observed predominately at the ABS of trailing poles (3'2). This magnetization reversal mechanism is believed to be introduced by the combined effects of eddy current damping and local magnetization saturation, and is consistent with the model proposed by Wood and Williams.

High Frequency Magnetic Force Microscopy-Imaging of Harddisk Write Heads

“…Measuring dynamics of a magnetic stray field in a submicron region has played important role in developing write heads. Several groups have successfully observed the dynamic magnetic field behavior by electron beam tomography 1,2) in a vacuum condition or magneto-optical methods [3][4][5][6] which detect magnetization on write heads. Recently, a useful method to observe the force interaction due to high frequency magnetic stray fields with the magnetic force microscope was proposed, called high-frequency magnetic force microscope (HF-MFM).…”