Time-domain study of microtrack structure and artifacts

To study the microtrack signal, noise and track “skirts” a time-domain technique [A. Taratorin, M. Xiao, and K. Klaassen, IEEE Trans. Mag. 40, 129 (2004)] was used. It shows that the standard microtrack preparation (two-sided dc erasure) suffers from demagnetization caused by the write head fringe fields. Low density micro-track tail signals were studied by analyzing read-back wave forms at different offset locations from the microtrack center. It was established that the tail-related signal is generated by cross-track medium magnetization. The dependence of this tail signal on the medium orientation ratio (OR) is studied; the tail signal amplitude decreases for higher OR media. An improved microtrack preparation procedure is presented, using two-sided multiple-pass repetitive dc erasure. It is demonstrated that the procedure reduces the tail artifacts due to the smaller cross-track component of the far-away write head field