Determination of Average Demagnetizing Fields in Longitudinal Magnetic Recording Using Nanosecond Field Pulses

Published

September 4, 2000

Author(s)

A Moser, D Weller, N D. Rizzo, Thomas J. Silva

Abstract

The demagnetizing field across bit transitions in longitudinal recording media is measuredquantitatively as a function of linear density using a quasi static write/read tester. Bit transitions with varying linear densities in the range 500-6000 flux changes per mm are recorded on CoCr₁₀Ta₄ media films. The media are deposited onto a coplanar waveguide structure, which is used to generate reversal field pulses of well-defined amplitude and 10 ns width to minimize thermally activated processes. The demagnetizing field is extracted from the measured reversal field, which is the sum of the external waveguide field and the internal, density-dependent demagnetizing field. The experimental results are qualitatively consistent with those predicted by a simple magnetostatic model that assumes finite transition widths.

Citation

Applied Physics Letters

Volume

77

Issue

10

Pub Type

Journals

Keywords

coplanar, demagnetizing fields, magnetic recording, quasi static tester, thin film media, waveguide

Citation

Moser, A. , Weller, D. , Rizzo, N. and Silva, T. (2000), Determination of Average Demagnetizing Fields in Longitudinal Magnetic Recording Using Nanosecond Field Pulses, Applied Physics Letters (Accessed October 14, 2025)