hesela.devPole erasure
Pole erasure is unintended disturbance of recorded data by a write pole's residual magnetic field after the write current has stopped.
The field comes from remanent magnetization in the writer, not necessarily from an external magnet. It is distinct from a thermal reversal in an isolated media grain and from interference caused by deliberately writing a neighboring track [1].
Experiments with fabricated single-pole writers found that shortening the main-pole throat could suppress remanence-related erasure in the tested geometry [2]. Geometry and magnetic-domain behavior matter; turning off current does not prove that the local magnetic field is zero.
Relations
- related
- pmr, magnetic-anisotropy, adjacent-track-interference, superparamagnetic-limit
Citations
- HGST: Perpendicular Magnetic Recording Technology, November 2007, pp. 1-4; hosted by Western Digital
- Nakamoto et al.: Single-Pole/TMR Heads for 100Gb/in2 Perpendicular Recording (2003), doi:10.3379/jmsjmag.27.124
Sources & caveats
- Nakamoto et al., 2003: publisher abstract reviewed; scanned full text obtained but not text-reviewed. No dimensional threshold or numerical outcome is generalized.
- The 2007 HGST explanation is historical component engineering, not a measured failure rate for present-day drives.