title: Dzyaloshinskii-Moriya Interaction and Spiral Order in Spin-orbit Coupled Optical Lattices.
abstract: We show that the recent experimental realization of spin-orbit coupling in ultracold atomic gases can be used to study different types of spin spiral order and resulting multiferroic effects. Spin-orbit coupling in optical lattices can give rise to the Dzyaloshinskii-Moriya (DM) spin interaction which is essential for spin spiral order. By taking into account spin-orbit coupling and an external Zeeman field, we derive an effective spin model in the Mott insulator regime at half filling and demonstrate that the DM interaction in optical lattices can be made extremely strong with realistic experimental parameters. The rich finite temperature phase diagrams of the effective spin models for fermions and bosons are obtained via classical Monte Carlo simulations.
authors.affiliation: 1] Department of Physics, the University of Texas at Dallas, Richardson, Texas, 75080 USA [2] Department of Physics and Center for Quantum Coherence, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Gong
authors.affiliation: Department of Physics, the University of Texas at Dallas, Richardson, Texas, 75080 USA.
authors.forename: Yinyin
authors.initials: Y
authors.lastname: Qian
authors.affiliation: Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 USA.
authors.forename: Mi
authors.initials: M
authors.lastname: Yan
authors.affiliation: Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 USA.
authors.forename: V W
authors.initials: VW
authors.lastname: Scarola
authors.affiliation: Department of Physics, the University of Texas at Dallas, Richardson, Texas, 75080 USA.
authors.forename: Chuanwei
authors.initials: C
authors.lastname: Zhang