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Gapless vortex bound states in superconducting topological semimetals.

ABSTRACT: We find that the vortex bound states in superconducting topological semimetals are gapless owing to topological massless excitations in their normal states. We demonstrate this universal result in a variety of semimetals, including Dirac and Weyl semimetals, three-fold degenerate spin-1 fermions, spin-3/2 Rarita-Schwinger-Weyl fermion semimetals and other exotic fermion semimetals. The formation of these gapless bound states is closely related to their Andreev specular reflection and propagating Andreev modes in π-phase superconductor-normal metal-superconductor junctions. We further demonstrate that these gapless states are topologically protected and can be derived from a topological pumping process.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC10016197 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Gapless vortex bound states in superconducting topological semimetals.

Zhang Yi Y Qin Shengshan S Jiang Kun K Hu Jiangping J

National science review 20220624 2

We find that the vortex bound states in superconducting topological semimetals are gapless owing to topological massless excitations in their normal states. We demonstrate this universal result in a variety of semimetals, including Dirac and Weyl semimetals, three-fold degenerate spin-1 fermions, spin-3/2 Rarita-Schwinger-Weyl fermion semimetals and other exotic fermion semimetals. The formation of these gapless bound states is closely related to their Andreev specular reflection and propagating ...[more]

PMID: 36935934

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