{
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-18",
  "slug": "magnetic-tunnel-junction",
  "term": "Magnetic tunnel junction",
  "aliases": [
    "MTJ"
  ],
  "definition": "A magnetic tunnel junction consists of two magnetic layers separated by a thin insulating barrier through which electrons tunnel.",
  "note": "Readout: In conventional MRAM junctions, parallel layer magnetizations give lower resistance and antiparallel magnetizations higher resistance. A reference layer and switchable free layer provide distinguishable states. [toggle]\n\nRole: The junction is a device structure, not a write protocol. STT-MRAM switches the free layer using current through it; field-switched MRAM uses a different write mechanism. [stt] [toggle]\n\nLimits: Barrier material, interfaces and applied electrical stress influence breakdown, so a measured junction lifetime is specific to the tested structure and conditions. [choi]",
  "related": [
    "mram",
    "stt-mram",
    "tunnel-magnetoresistive-head",
    "magnetic-anisotropy"
  ],
  "citations": [
    {
      "id": "toggle",
      "title": "Everspin: Toggle MRAM Technology, cell structure and read/write operation.",
      "url": "https://legacy.everspin.com/toggle-mram-technology",
      "accessed": "2026-10-18"
    },
    {
      "id": "stt",
      "title": "Everspin: STT-MRAM Technology, switching mechanism and interface examples.",
      "url": "https://www.everspin.com/stt-mram-technology",
      "accessed": "2026-10-18"
    },
    {
      "id": "choi",
      "title": "Choi et al. (2017). Endurance of magnetic tunnel junctions under dynamic voltage stress. Electronics Letters 53:1146-1148.",
      "url": "https://ietresearch.onlinelibrary.wiley.com/doi/10.1049/el.2017.1579",
      "accessed": "2026-10-18"
    },
    {
      "id": "hesela-mram",
      "title": "Hesela: Magnetoresistive RAM (MRAM).",
      "url": "https://hesela.com/tech/mram/",
      "accessed": "2026-10-18"
    }
  ],
  "provenance": [
    "The cited endurance experiment used MgAl2O4 barriers. Its cycle counts are not generalized to other barrier materials. [choi]"
  ]
}