{
  "abstract": "We report the first successful growth of stoichiometric hexagonal TiAs single crystals (space group $P6_3/mmc$) using chemical vapor transport and investigate their vibrational, electronic, topological, and magnetotransport properties. Polarized Raman spectroscopy identifies all four Raman-active phonon modes ($A_{1g} + E_{1g} + 2E_{2g}$), consistent with the hexagonal crystal symmetry. First-principles calculations reveal nontrivial band topology characterized by a symmetry indicator $\\mathbb{Z}_4 = 2$ and a strong topological index $ν_0 = 1$, together with symmetry-protected fourfold band degeneracies at the nonsymmorphic Brillouin-zone boundary. The Fermi surface exhibits an orbital-dependent crossover from quasi-two-dimensional cylindrical sheets to a corrugated three-dimensional structure along $k_z$. A Van Hove saddle point approximately 0.5 eV below the Fermi level along $Γ\\text{--}K$ is associated with a neck-disrupting Lifshitz transition and enhanced density of states. Magnetotransport measurements reveal a pronounced twofold angular magnetoresistance, consistent with anisotropic Fermi-surface geometry and open cyclotron orbits. Hall measurements indicate uncompensated, hole-dominated transport, accounting for the absence of extreme magnetoresistance and contributing to the field-orientation-dependent Hall response. These results establish hexagonal TiAs as a platform for exploring the interplay of nonsymmorphic band topology, Van Hove singularities, and anisotropic electronic transport in transition-metal monopnictides.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.12925",
  "author_total": 11,
  "authors": [
    {
      "name": "Azizur Rahman"
    },
    {
      "name": "Shashi B Mishra"
    },
    {
      "name": "Sheraz Khan"
    },
    {
      "name": "Khushnood Shah"
    },
    {
      "name": "Xun Ma"
    },
    {
      "name": "Xiaoyang Lin"
    },
    {
      "name": "Tomasz Sobol"
    },
    {
      "name": "Lei Zhang"
    },
    {
      "name": "Weisheng Zhao"
    },
    {
      "name": "Min Zhang"
    },
    {
      "name": "Zahir Muhammad"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6xve6yx3sdv3j.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.12925",
  "fulltext_url": null,
  "id": "6xve6yx3sdv3j",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.12925",
  "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",
      "cond-mat.mtrl-sci"
    ],
    [
      "openalex",
      "3107|Topological Materials and Phenomena"
    ]
  ],
  "openalex": "W7221548673",
  "pdf_url": "https://arxiv.org/pdf/2610.12925",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6xve6yx3sdv3j.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:28:36Z",
      "native_id": "2610.12925",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.12925"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Symmetry-Enforced Topology and Van Hove Saddle Points in Hexagonal TiAs",
  "title_text": "Symmetry-Enforced Topology and Van Hove Saddle Points in Hexagonal TiAs",
  "type": "preprint",
  "updated_at": "2026-10-30T12:28:36Z",
  "url": "https://research.draconitic.com/paper/6xve6yx3sdv3j",
  "venue": "arXiv",
  "versions": []
}