{
  "abstract": "Fast, precise, and quantum-non-demolition (QND) readout of superconducting qubits is a fundamental component of high-fidelity quantum sensing and computation. Conventional approaches typically operate in the dispersive regime, where the qubit-resonator coupling $g$ is weak compared to the detuning $Δ$. While exhibiting good QND properties, the readout rate is limited to $\\sim g^2\\sqrt{N}/Δ\\ll g$, where $N$ is the number of photons in the resonator. QND readout in the nondispersive regime, where the readout rate reaches its full potential $\\sim g$, relies on parameter sweeps that may encounter resonances, leading to measurement-induced state transitions (MIST). In this work, we study a nondispersive readout protocol that replaces these sweeps by sudden quenches of the coupling constant, using a resonator that is preloaded with photons. We call this protocol bang-bang readout, and show that it realizes single-shot projective measurements. The fidelity and QNDness of the qubit post-measurement are remarkably high, with an error that decreases like $1/N$. We show that the protocol can also be implemented without preloading the resonator by instead strongly driving the qubit, e.g., with a classical flux drive.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.23681",
  "author_total": 4,
  "authors": [
    {
      "name": "Nina del Ser"
    },
    {
      "name": "Yinan Chen"
    },
    {
      "name": "Jacob Steiner"
    },
    {
      "name": "Gil Refael"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3m7yh79h1xyrn.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.23681",
  "fulltext_url": null,
  "id": "3m7yh79h1xyrn",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.23681",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7204276541",
  "pdf_url": "https://arxiv.org/pdf/2608.23681",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-17",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/3m7yh79h1xyrn.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:03Z",
      "native_id": "2608.23681",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.23681"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Bang-bang protocol for nondispersive qubit readout",
  "title_text": "Bang-bang protocol for nondispersive qubit readout",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:03Z",
  "url": "https://research.draconitic.com/paper/3m7yh79h1xyrn",
  "venue": "arXiv",
  "versions": []
}