Sine-Gordon description of Beresinskii-Kosterlitz-Thouless vortices in superconductors immersed in an external magnetic field.

{
  "study_type": "other",
  "exposure": {
    "band": null,
    "source": "external magnetic field",
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": null,
  "sample_size": null,
  "outcomes": [
    "Field-induced magnetization",
    "Nonlinear effects at low fields above the transition",
    "Correlation length divergence (BKT theory)"
  ],
  "main_findings": "Using a sine-Gordon field-theoretical approach, the authors describe BKT vortices in two-dimensional superconductors at finite magnetic field and provide a definition of field-induced magnetization. They report that persistence of nonlinear effects at low fields above the transition is a signature of rapid divergence of the correlation length within BKT theory.",
  "effect_direction": "unclear",
  "limitations": [
    "The abstract describes a theoretical/modeling approach; no experimental or epidemiological data are reported.",
    "No quantitative exposure parameters (e.g., field strength) are provided in the abstract."
  ],
  "evidence_strength": "insufficient",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "Beresinskii-Kosterlitz-Thouless",
    "BKT",
    "vortices",
    "two-dimensional superconductors",
    "external magnetic field",
    "sine-Gordon model",
    "magnetization",
    "correlation length",
    "nonlinear effects"
  ],
  "suggested_hubs": []
}