Paper

{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2603.11637v1</id>\n    <title>Double-twisted surface spectrum from hybridized Majorana Kramers pairs and wallpaper fermions</title>\n    <updated>2026-03-12T07:57:35Z</updated>\n    <link href='https://arxiv.org/abs/2603.11637v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2603.11637v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>We theoretically investigate the superconducting surface states of wallpaper fermions, which are surface quasiparticles of topological nonsymmorphic crystalline insulators protected by a wallpaper group $p4g$ symmetry, based on a tight-binding model for the space group $P4/mbm$ (No. 127). A symmetry-based analysis shows that four types of on-site pair potentials are allowed. Using the symmetries of the wallpaper group $p4g$ and the one-dimensional topological invariants, we clarify that for the $\\mathrm{A_{1u}}$ representation, wallpaper fermions and two Majorana Kramers pairs coexist, and hybridization between them give rise to a double-twisted surface state and produces four peaks in the surface density of states. We further find that the mirror Chern number vanishes, indicating that our system realizes mirror-helicity-free surface states. This distinguishes superconducting wallpaper fermions from the other superconducting topological (crystalline) insulators, such as $\\mathrm{Cu}_x\\mathrm{Bi}_2\\mathrm{Se}_3$ and $\\mathrm{Sn}_{1-x}\\mathrm{In}_x\\mathrm{Te}$.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='cond-mat.supr-con'/>\n    <published>2026-03-12T07:57:35Z</published>\n    <arxiv:comment>9 pages, 6 figures</arxiv:comment>\n    <arxiv:primary_category term='cond-mat.supr-con'/>\n    <author>\n      <name>Kaito Yoda</name>\n    </author>\n    <author>\n      <name>Ai Yamakage</name>\n    </author>\n  </entry>"
}