{
 "schema_version": "0.2",
 "name": "[[49,1,7]] surface code",
 "code_type": "CSS",
 "n": 49,
 "k": 1,
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 },
 "provenance": {
  "authors": [
   "Kitaev, A. Yu."
  ],
  "origin": "baseline",
  "construction": "Rotated surface code, distance 7.",
  "date": "1997-07-09",
  "references": [
   "arXiv:quant-ph/9707021"
  ],
  "notes": "Distance is exact by construction. 2D layout added 2026-07-23: qubit q at (q//7, q%7) on the 7x7 planar grid; single layer, measured interaction radius sqrt(2)."
 },
 "family": "topological",
 "locality": {
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  "interaction_radius": 1.4142135623730951,
  "layers": 1
 },
 "circuit": {
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    "witness": [
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  "rounds": 7,
  "stim_version": "1.16.0",
  "notes": "standard geometric zigzag schedule (X pattern 'n', Z pattern 'z') derived from the 2D layout; generated by research/circuit_seed.py"
 }
}