Gong Ming, Qian Yinyin, Yan Mi, Scarola V W, Zhang Chuanwei
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.
Department of Physics, the University of Texas at Dallas, Richardson, Texas, 75080 USA.
Sci Rep. 2015 May 27;5:10050. doi: 10.1038/srep10050.
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.
我们表明，最近在超冷原子气体中实现的自旋轨道耦合实验可用于研究不同类型的自旋螺旋序以及由此产生的多铁性效应。光学晶格中的自旋轨道耦合可产生对自旋螺旋序至关重要的Dzyaloshinskii-Moriya（DM）自旋相互作用。通过考虑自旋轨道耦合和外部塞曼场，我们推导了半填充时莫特绝缘体区域的有效自旋模型，并证明在实际实验参数下，光学晶格中的DM相互作用可以变得极强。通过经典蒙特卡罗模拟获得了费米子和玻色子有效自旋模型丰富的有限温度相图。
