{
  "abstract": "An important feature of solid-state or cold atom systems in low dimensions is the restricted oscillations of ionic/atomic degrees of freedom in the confining directions, for which the conventional phonon from canonical quantization is not an ideal description. In this work we propose a general recipe to introduce this feature to otherwise unrestricted systems by mapping displacement fields to spin degrees of freedom, dubbed soft-corization. In the strong-confinement limit $S=1/2$, we demonstrate the validity of the approach with a harmonic chain; the results lead to a gapped fermionic model showing the absence of acoustic modes as a signature of the confinement of the entire chain. Despite the non-conserved total particle number in the presence of nearest-neighbor parings, the model holds a coarse-grained $U(1)$ symmetry with conserved polarization charge in the absence of nearest-neighbor hopping. This enables a new transport mechanism via \"dimer-tumbling\" instead of single-particle hopping. We then introduce a short-range interaction via anharmonicity; for energy scales slightly above the gap, it leads to a (quantum) phase transition to a nonreciprocal state carrying polarization charge current and heat current with spontaneous time reversal symmetry breaking (TRSB) of the type $\\hat{T}^2=+1$. The non-reciprocity can be probed by measuring the change of inductance due to gauge fields in and out of the ordered phase.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2607.14232",
  "author_total": 2,
  "authors": [
    {
      "name": "Yuan Gao"
    },
    {
      "name": "K. A. Muttalib"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8yy5xeww3nfg5.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.14232",
  "fulltext_url": null,
  "id": "8yy5xeww3nfg5",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.14232",
  "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",
      "cond-mat.mes-hall"
    ],
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.quant-gas"
    ],
    [
      "openalex",
      "3107|Topological Materials and Phenomena"
    ]
  ],
  "openalex": "W7169513583",
  "pdf_url": "https://arxiv.org/pdf/2607.14232",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-13",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8yy5xeww3nfg5.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:11Z",
      "native_id": "2607.14232",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.14232"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.quant-gas",
      "subfield": "amo"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mes-hall",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Phonons under confinement: Coarse-grained $U(1)$ charge and a new transport mechanism",
  "title_text": "Phonons under confinement: Coarse-grained U(1) charge and a new transport mechanism",
  "type": "preprint",
  "updated_at": "2026-11-09T00:20:12Z",
  "url": "https://research.draconitic.com/paper/8yy5xeww3nfg5",
  "venue": "arXiv",
  "versions": []
}