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, threefold degenerate spin-1 fermions, spin-3/2 Rarita-Schwinger-Weyl fermion semimetals and other exotic fermion semimetals. The formation of these gapless bound states are closely related to their Andreev specular reflection and propagating Andreev modes in $\pi$ phase superconductor-normal metal-superconductor (SNS) junctions. We further demonstrate that these gapless states are topologically protected and can be derived from a topological pumping process.

5 pages, 4 figures

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Cited by in corpus (5)

• Observation of the topological Dirac fermions and surface states in superconducting BaSn3
• Crystal-symmetry-protected gapless vortex-line phases in superconducting Dirac semimetals
• Double Majorana Vortex Flat Bands in the Topological Dirac Superconductor
• Majorana Flat Bands in the Vortex Line of Superconducting Weyl Semimetals
• Majorana vortex phases in time-reversal invariant higher-order topological insulators and topologically trivial insulators