Bakhtiari M Reza, Hemmerich A, Ritsch H, Thorwart M
I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
Institut für Laser-Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
Phys Rev Lett. 2015 Mar 27;114(12):123601. doi: 10.1103/PhysRevLett.114.123601. Epub 2015 Mar 25.
We investigate the nonlinear light-matter interaction of a Bose-Einstein condensate trapped in an external periodic potential inside an optical cavity which is weakly coupled to vacuum radiation modes and driven by a transverse pump field. Based on a generalized Bose-Hubbard model which incorporates a single cavity mode, we include the collective backaction of the atoms on the cavity light field and determine the nonequilibrium quantum phases within the nonperturbative bosonic dynamical mean-field theory. With the system parameters adapted to recent experiments, we find a quantum phase transition from a normal phase to a self-organized superfluid phase, which is related to the Hepp-Lieb-Dicke superradiance phase transition. For even stronger pumping, a self-organized Mott insulator phase arises.
我们研究了被困在外部周期性势中的玻色 - 爱因斯坦凝聚体在光学腔内的非线性光与物质相互作用，该光学腔与真空辐射模式弱耦合，并由横向泵浦场驱动。基于包含单个腔模的广义玻色 - 哈伯德模型，我们考虑了原子对腔光场的集体反作用，并在非微扰玻色子动态平均场理论内确定非平衡量子相。通过使系统参数适应最近的实验，我们发现了从正常相到自组织超流相的量子相变，这与赫普 - 利布 - 迪克超辐射相变有关。对于更强的泵浦，会出现自组织莫特绝缘体相。
