Yin Honghao, Hu Jie, Ji An-Chun, Juzeliūnas Gediminas, Liu Xiong-Jun, Sun Qing
Department of Physics, Capital Normal University, Beijing 100048, China.
Institute of Theoretical Physics and Astronomy, Vilnius University, Saulėtekio 3, LT-10257 Vilnius, Lithuania.
Phys Rev Lett. 2020 Mar 20;124(11):113601. doi: 10.1103/PhysRevLett.124.113601.
The prominent Dicke superradiant phase arises from coupling an ensemble of atoms to a cavity optical field when an external optical pumping exceeds a threshold strength. Here we report a prediction of the superradiant instability driven by Anderson localization, realized with a hybrid system of the Dicke and Aubry-André (DAA) model for bosons trapped in a one-dimensional (1D) quasiperiodic optical lattice and coupled to a cavity. Our central finding is that for bosons condensed in a localized phase given by the DAA model, the resonant superradiant scattering is induced, for which the critical optical pumping of the superradiant phase transition approaches zero, giving an instability driven by the Anderson localization. The superradiant phase for the DAA model with or without a mobility edge is investigated, showing that the localization driven superradiant instability is in sharp contrast to the superradiance as widely observed for a Bose-Einstein condensate in extended states, and should be insensitive to the temperature of the system. This study unveils a novel effect of localization on the Dicke superradiance, and is well accessible based on the current experiments.
当外部光泵浦超过阈值强度时，显著的迪克超辐射相源于将一组原子与腔光场耦合。在此，我们报告了由安德森局域化驱动的超辐射不稳定性的预测，这是通过玻色子的迪克和奥布里 - 安德烈（DAA）模型的混合系统实现的，该玻色子被困在一维（1D）准周期光学晶格中并与腔耦合。我们的核心发现是，对于凝聚在由DAA模型给出的局域相中的玻色子，会诱导出共振超辐射散射，其超辐射相变的临界光泵浦趋近于零，从而产生由安德森局域化驱动的不稳定性。我们研究了有无迁移率边缘的DAA模型的超辐射相，结果表明，局域化驱动的超辐射不稳定性与在扩展态的玻色 - 爱因斯坦凝聚中广泛观察到的超辐射形成鲜明对比，并且应该对系统温度不敏感。这项研究揭示了局域化对迪克超辐射的一种新效应，并且基于当前实验很容易实现。
