Quartet Superfluid in Two-dimensional Mass-imbalanced Fermi Mixtures
Abstract
Quartet superfluid (QSF) is a distinct type of fermion superfluidity that exhibits high-order correlation beyond the conventional BCS pairing paradigm. In this Letter, we report the emergent QSF in 2D mass-imbalanced Fermi mixtures with two-body contact interactions. This is facilitated by the formation of quartet bound state in vacuum that consists of a light atom and three heavy fermions. For an optimized heavy-light number ratio , we identify QSF as the ground state in a considerable parameter regime of mass imbalance and 2D coupling strength. Its unique high-order correlation can be manifested in the momentum-space crystallization of pairing field and density distribution of heavy fermions. Our results can be readily detected in Fermi-Fermi mixtures nowadays realized in cold atoms laboratories, and meanwhile shed light on exotic superfluidity in a broad context of mass-imbalanced fermion mixtures.
Cite
@article{arxiv.2305.05831,
title = {Quartet Superfluid in Two-dimensional Mass-imbalanced Fermi Mixtures},
author = {Ruijin Liu and Wei Wang and Xiaoling Cui},
journal= {arXiv preprint arXiv:2305.05831},
year = {2023}
}
Comments
7+8 pages, 3+5 figures