Itinerant chiral ferromagnetism in a trapped Rashba spin-orbit-coupled Fermi gas

Shang-Shun Zhang, Wu-Ming Liu, Han Pu
2016 Physical Review A  
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
more » ... -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.
doi:10.1103/physreva.93.043602 fatcat:mt6plmpvijdfzh7pzvhuegltya