Possible pairing mechanism switching driven by structural symmetry breaking in BiS2-based layered superconductors

Bibliographic Details
Title: Possible pairing mechanism switching driven by structural symmetry breaking in BiS2-based layered superconductors
Authors: Yamashita, Aichi, Usui, Hidetomo, Hoshi, Kazuhisa, Goto, Yosuke, Kuroki, Kazuhiko, Mizuguchi, Yoshikazu
Source: Sci. Rep. 11, 230(1-7) (2021)
Publication Year: 2020
Collection: Condensed Matter
Subject Terms: Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
More Details: Investigation of isotope effects on superconducting transition temperature (Tc) is one of the useful methods to examine whether electron-phonon interaction is essential for pairing mechanisms. The layered BiCh2-based (Ch: S, Se) superconductor family is a candidate for unconventional superconductors, because unconventional isotope effects have previously been observed in La(O,F)BiSSe and Bi4O4S3. In this study, we investigated the isotope effects of 32S and 34S in the high-pressure phase of (Sr,La)FBiS2, which has a monoclinic crystal structure and a higher Tc of 10 K under high pressures, and observed conventional-type isotope shifts in Tc. The conventional-type isotope effects in the monoclinic phase of (Sr,La)FBiS2 are different from the unconventional isotope effects observed in La(O,F)BiSSe and Bi4O4S3, which have a tetragonal structure. The obtained results suggest that the pairing mechanisms of BiCh2-based superconductors could be switched by a structural-symmetry change in the superconducting layers induced by pressure effects.
Comment: 18 pages, 3 figures, 1 table, supplementary file
Document Type: Working Paper
DOI: 10.1038/s41598-020-80544-2
Access URL: http://arxiv.org/abs/2007.11130
Accession Number: edsarx.2007.11130
Database: arXiv
More Details
DOI:10.1038/s41598-020-80544-2