{
  "abstract": "Synthesizing arbitrary $n$-qubit unitaries using as few non-Clifford gates as possible is a central problem in fault-tolerant quantum compilation. We present a Clifford+$T$ quantum circuit construction that approximately implements any classically specified unitary to within error $ε$ and achieves a worst-case $T$-count with leading exponential scaling of $2^{5n/4}$ whenever $\\log(1/ε)=\\operatorname{poly}(n)$. This improves upon the best previous $2^{4n/3}$ scaling. The key innovation lies in treating the target unitary as a single block-encoded object rather than a long product of simpler operations. A technique of block flattening controls the normalization while preserving an efficient implementation of the block encoding; subsequently, quantum singular value transformation maps its common singular value to one, thereby recovering the target unitary.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.17846",
  "author_total": 3,
  "authors": [
    {
      "name": "Pei Yuan"
    },
    {
      "name": "Shengyu Zhang"
    },
    {
      "name": "Wei Zi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/49cc2967wn50c.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.17846",
  "fulltext_url": null,
  "id": "49cc2967wn50c",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.17846",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "1702|Quantum Computing Algorithms and Architecture"
    ]
  ],
  "openalex": "W7203750576",
  "pdf_url": "https://arxiv.org/pdf/2608.17846",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-30",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/49cc2967wn50c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:41Z",
      "native_id": "2608.17846",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.17846"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Quantum Circuit for General Unitary: Improved T-count via Block Flattening and Dilation",
  "title_text": "Quantum Circuit for General Unitary: Improved T-count via Block Flattening and Dilation",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:41Z",
  "url": "https://research.draconitic.com/paper/49cc2967wn50c",
  "venue": "arXiv",
  "versions": []
}