Title
Bulk odd-frequency pairing in the superconducting Su-Schrieffer-Heeger model
Date Issued
01 June 2020
Access level
open access
Resource Type
journal article
Author(s)
Uppsala University
Publisher(s)
American Physical Society
Abstract
The Su-Schrieffer-Heeger model describes fermions that hop on a one-dimensional chain with staggered hopping amplitude, where the unit cell contains two sites, or two sublattices. In this work we consider the Su-Schrieffer-Heeger model with superconducting pairing and show that the sublattice index acts as an additional quantum number in the classification of Cooper pairs, giving rise to inter- A nd intrasublattice odd-frequency pair correlations in the bulk. Interestingly, this system behaves as a two-band superconductor where the bulk odd-frequency correlations depend solely on the intrinsic staggering properties of the model. In general, odd-frequency correlations coexist with even-frequency correlations in both the trivial and topological phases, with comparable and even larger odd-frequency amplitudes at the topological phase transition points at low frequencies, due to the closing of the energy gap at these points. Furthermore, we also discuss how bulk odd-frequency amplitudes are correlated with pseudogaps in the density of states and also with a charge density wave that appears due to the chemical potential imbalance between sublattices.
Volume
101
Issue
21
Language
English
OCDE Knowledge area
Física de partículas, Campos de la Física
Astronomía
Scopus EID
2-s2.0-85086994227
Source
Physical Review B
ISSN of the container
24699950
Sponsor(s)
We thank P. Burset and O. A. Awoga for helpful discussions. S.T., S.N., and Y.T. acknowledge the support from Grant-in-Aid for Scientific Research on Innovative Areas, Topological Material Science (Grants No. JP15H05851, No. JP15H05853, and No. JP15K21717) and Grant-in-Aid for Scientific Research B (KAKENHI Grant No. JP18H01176) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan (MEXT) and JST CREST Grant No. JPMJCR16F2. Y.T. is also supported by Scientific Research A (KAKENHI Grant No. JP20H00131) and JSPS Core-to-Core program “Oxide Superspin international network“. A.B.S. and J.C. acknowledge support from the Swedish Research Council (Vetenskapsrådet Grant No. 2018-03488), the Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program, and the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (Grant No. ERC-2017-StG-757553).
Sources of information:
Directorio de Producción Científica
Scopus