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Chiral superconductivity in the alternate stacking compound 4Hb-TaS2.

ABSTRACT: Van der Waals materials offer unprecedented control of electronic properties via stacking of different types of two-dimensional materials. A fascinating frontier, largely unexplored, is the stacking of strongly correlated phases of matter. We study 4Hb-TaS2, which naturally realizes an alternating stacking of 1T-TaS2 and 1H-TaS2 structures. The former is a well-known Mott insulator, which has recently been proposed to host a gapless spin-liquid ground state. The latter is a superconductor known to also host a competing charge density wave state. This raises the question of how these two components affect each other when stacked together. We find a superconductor with a Tc of 2.7 Kelvin and anomalous properties, of which the most notable one is a signature of time-reversal symmetry breaking, abruptly appearing at the superconducting transition. This observation is consistent with a chiral superconducting state.

SUBMITTER: Ribak A

PROVIDER: S-EPMC7101217 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Chiral superconductivity in the alternate stacking compound 4Hb-TaS2.

Ribak A A Skiff R Majlin RM Mograbi M M Rout P K PK Fischer M H MH Ruhman J J Chashka K K Dagan Y Y Kanigel A A

Science advances 20200327 13

Van der Waals materials offer unprecedented control of electronic properties via stacking of different types of two-dimensional materials. A fascinating frontier, largely unexplored, is the stacking of strongly correlated phases of matter. We study 4Hb-TaS2, which naturally realizes an alternating stacking of 1T-TaS2 and 1H-TaS2 structures. The former is a well-known Mott insulator, which has recently been proposed to host a gapless spin-liquid ground state. The ...[more]

PMID: 32258393

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