Abstract
We suggest that an inhomogeneous (nonzero-momentum) paired phase can appear in the absence of an external magnetic field in a system with a predominant interband pairing and with separate Fermi-surface sheets. The Fermi wave vector mismatch which appears in such a situation can be compensated by nonzero center-of-mass momentum of the Cooper pairs, which can lead to a spontaneous appearance of the Fulde-Ferrell type of superconducting state. The idea is examined using a tight-binding model which emulates the holelike and the electronlike bands of iron-based superconductors. The state can appear for the cases of both spin-singlet and spin-triplet pairing channels.
6 More- Received 14 April 2014
- Revised 27 October 2014
DOI:https://doi.org/10.1103/PhysRevB.90.174507
©2014 American Physical Society