{
  "status": "unknown",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-17",
  "slug": "pole-erasure",
  "term": "Pole erasure",
  "aliases": [],
  "definition": "Pole erasure is unintended disturbance of recorded data by a write pole's residual magnetic field after the write current has stopped.",
  "note": "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 [pmr-wd-white-paper].\n\nExperiments with fabricated single-pole writers found that shortening the main-pole throat could suppress remanence-related erasure in the tested geometry [nakamoto-2003]. Geometry and magnetic-domain behavior matter; turning off current does not prove that the local magnetic field is zero.",
  "related": [
    "pmr",
    "magnetic-anisotropy",
    "adjacent-track-interference",
    "superparamagnetic-limit"
  ],
  "citations": [
    {
      "id": "pmr-wd-white-paper",
      "title": "HGST: Perpendicular Magnetic Recording Technology, November 2007, pp. 1-4; hosted by Western Digital",
      "url": "https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/collateral/white-paper/white-paper-pmr.pdf",
      "accessed": "2026-10-17"
    },
    {
      "id": "nakamoto-2003",
      "title": "Nakamoto et al.: Single-Pole/TMR Heads for 100Gb/in2 Perpendicular Recording (2003), doi:10.3379/jmsjmag.27.124",
      "url": "https://www.jstage.jst.go.jp/article/jmsjmag/27/3/27_3_124/_article/-char/en",
      "accessed": "2026-10-17"
    }
  ],
  "provenance": [
    "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."
  ]
}