{
  "abstract": "Magic-angle twisted bilayer graphene (MATBG) hosts flat bands whose correlated and topological phases depend sensitively on the electronic point-group symmetry, which is set by the device configuration including twist angle, heterostrain, and substrate and cap-layer coupling. Here we report near-infrared photocurrent measurements of a MATBG device encapsulated by an hBN substrate and a WSe$_2$ cap layer, at a twist angle of 1.05°. Using spatially resolved photocurrent imaging with polarization analysis, we disentangle the photothermoelectric response from the circular photogalvanic effect (CPGE) across all fillings of the moiré flat bands. A finite CPGE at normal incidence, forbidden in high-symmetry structures, directly constrains the point-group symmetry of MATBG and reveals a Berry curvature dipole intrinsic to the MATBG flat bands, activated by the symmetry lowering from heterostrain and the asymmetric hBN/WSe$_2$ environment. Our results establish nonlinear photocurrent as an all-optical probe of symmetry and quantum geometry in proximity-engineered moiré materials.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.06389",
  "author_total": 10,
  "authors": [
    {
      "name": "Eylon Persky"
    },
    {
      "name": "Leonie Parisot"
    },
    {
      "name": "Minhao He"
    },
    {
      "name": "Jiaqi Cai"
    },
    {
      "name": "Takashi Taniguchi"
    },
    {
      "name": "Kenji Watanabe"
    },
    {
      "name": "Pierre A. Pantaleon"
    },
    {
      "name": "Francisco Guinea"
    },
    {
      "name": "Xiaodong Xu"
    },
    {
      "name": "Aharon Kapitulnik"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7ynrv5bj44bp6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.06389",
  "fulltext_url": null,
  "id": "7ynrv5bj44bp6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.06389",
  "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.str-el"
    ],
    [
      "openalex",
      "2505|Graphene research and applications"
    ]
  ],
  "openalex": "W7163675826",
  "pdf_url": "https://arxiv.org/pdf/2606.06389",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7ynrv5bj44bp6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2606.06389",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.06389"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.str-el",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Revealing quantum geometry effects in magic angle twisted bilayer graphene using the circular photogalvanic effect",
  "title_text": "Revealing quantum geometry effects in magic angle twisted bilayer graphene using the circular photogalvanic effect",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/7ynrv5bj44bp6",
  "venue": "arXiv",
  "versions": []
}