{
  "id": "2005.14557",
  "version": "v1",
  "published": "2020-05-29T13:14:45.000Z",
  "updated": "2020-05-29T13:14:45.000Z",
  "title": "Ab initio k.p theory of spin-momentum locking: Application to topological surface states",
  "authors": [
    "I. A. Nechaev",
    "E. E. Krasovskii"
  ],
  "comment": "8 pages, 3 figures, 2 tables",
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.other"
  ],
  "abstract": "Based on ab initio relativistic ${\\mathbf k}\\cdot{\\mathbf p}$ theory, we derive an effective two-band model for surface states of three-dimensional topological insulators up to seventh order in $\\mathbf{k}$. It provides a comprehensive description of the surface spin structure characterized by a non-orthogonality between momentum and spin. We show that the oscillation of the non-orthogonality with the polar angle of $\\mathbf{k}$ with a $\\pi/3$ periodicity can be seen as due to effective six-fold symmetric spin-orbit magnetic fields with a quintuple and septuple winding of the field vectors per single rotation of $\\mathbf{k}$. Owing to the dominant effect of the classical Rashba field, there remains a single-winding helical spin structure but with a periodic few-degree deviation from the orthogonal locking between momentum and spin.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-05-29T13:14:45.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "topological surface states",
      "ab initio",
      "spin-momentum locking",
      "six-fold symmetric spin-orbit magnetic fields",
      "effective six-fold symmetric spin-orbit magnetic"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 8,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}