Spin response and topology of a staggered-Rashba superconductor
Abstract
Inversion symmetry is a key symmetry in unconventional superconductors, and even its local breaking can have profound implications. For inversion-symmetric systems, there is a competition on a microscopic level between the spin-orbit coupling associated with the local lack of inversion and hybridizing terms that "restore" inversion. Investigating a layered system with alternating mirror-symmetry breaking, we study this competition considering the spin response of different superconducting order parameters for the case of strong spin-orbit coupling. We find that signatures of the local noncentrosymmetry, such as an increased spin susceptibility in spin-singlet superconductors for T →0 , persist even into the quasi-three-dimensional regime. This leads to a direction-dependent spin response that allows us to distinguish different superconducting order parameters. Furthermore, we identify several regimes with possible topological superconducting phases within a symmetry-indicator analysis. Our results may have direct relevance for the recently reported Ce-based superconductor CeRh2As2 and beyond.
- Publication:
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Physical Review Research
- Pub Date:
- August 2021
- DOI:
- 10.1103/PhysRevResearch.3.033133
- arXiv:
- arXiv:2103.06282
- Bibcode:
- 2021PhRvR...3c3133S
- Keywords:
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- Condensed Matter - Superconductivity
- E-Print:
- Phys. Rev. Research 3, 033133 (2021)