Itinerant chiral ferromagnetism in a trapped Rashba spin-orbit coupled Fermi gas
Abstract
How ferromagnetic phases emerge in itinerant systems is an outstanding problem in quantum magnetism. Here we consider a repulsive two-component Fermi gas confined in a two dimensional isotropic harmonic potential and subject to a large Rashba spin-orbit (SO) coupling, whose single-particle dispersion can be tailored by adjusting the SO coupling strength. We show that the interplay among SO coupling, correlation effects and mean-field repulsion leads to a competition between ferromagnetic and non-magnetic phases. At intermediate interaction strengths, ferromagnetic phase emerges which can be well described by the mean-field Hartree-Fock theory; whereas at strong interaction strengths, a strongly correlated non-magnetic phase is favored due to the beyond-mean-field quantum correlation effects. Furthermore, the ferromagnetic phase of this system possesses a chiral current density induced by the Rashba spin-orbit coupling, whose experimental signature is investigated.
Keywords
Cite
@article{arxiv.1509.04095,
title = {Itinerant chiral ferromagnetism in a trapped Rashba spin-orbit coupled Fermi gas},
author = {Shang-Shun Zhang and Wu-Ming Liu and Han Pu},
journal= {arXiv preprint arXiv:1509.04095},
year = {2016}
}
Comments
Main text: 5 pages, 6 figures; Supplement: 4 pages, 2 figures