Evidence for multiband gapless superconductivity in the topological superconductor candidate 4Hb-TaS2

2024/12/11 by Hanru Wang, Wang, Hanru, Yihan Jiao +19 · 2 citations
Materials Science · Chemistry · Physics and Astronomy · #Iron-based superconductors research #Inorganic Chemistry and Materials #Topological Materials and Phenomena

paper · pdf · doi:10.48550/arxiv.2412.08450

Abstract

We present the ultralow-temperature thermal conductivity measurements on single crystals of transition-metal dichalcogenide material 4Hb-TaS₂, which has recently been proposed as a topological superconductor candidate. In zero field, a small residual linear term κ₀/T is observed, indicating the existence of a residual density of states in the superconducting state. The slow field dependence of κ₀/T at low fields rules out the presence of nodes in the superconducting gap, and the S-shaped field dependence across the full field range suggests multiple superconducting gaps in 4Hb-TaS₂. Our results provide evidence for multiband gapless superconductivity in 4Hb-TaS₂, and the residual density of states come from certain gapless Fermi surfaces.

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