Ordered states of Rydberg-dressed ultracold quantum gases in optical lattices

研究了光晶格中里德伯修饰量子气体的长程有序态和准粒子激发。我们的非微扰理论方法，基于扩展的哈伯德模型，使我们能够解决从远失谐弱敷料共振里德伯激发的全部参数范围。它包括由敷料引起的集体多体相互作用，这超出了基于有效对势的描述。利用动力学平均场理论（DMFT），我们计算了超流、超固体、密度有序相和自旋有序相，以及它们的临界温度和临界熵。我们研究了几何晶格挫挫对相图的影响，这有望导致新的关联态。我们确定集体模式，如希格斯振幅模式，和准粒子色散的穿着系统，应用广义玻色子准粒子理论。耗散和退相的额外影响，为现实的里德伯激光激发计划内的Lindblad主方程，解决非微扰，这使我们能够计算出完整的平衡稳态相图，并寻找新的有序状态，这是稳定的耗散。

We investigate long-range ordered states and quasiparticle excitations of Rydberg-dressed quantum gases in optical lattices. Our non-perturbative theoretical approach, based on an extended Hubbard model, allows us to address the full parameter range from far-detuned weak dressing to resonant Rydberg excitation. It includes collective many-body interactions induced by dressing, which are beyond descriptions based on effective pair potentials. Using dynamical mean-field theory (DMFT), we calculate superfluid, supersolid, density- and spin-ordered phases, as well as their critical temperatures and entropies. We investigate the influence of geometric lattice frustration on the phase diagram, which is expected to lead to novel correlated states. We determine collective modes, such as the Higgs-amplitude mode, and quasiparticle dispersions of the dressed system, applying a generalized bosonic quasiparticle-theory. The additional influence of dissipation and dephasing for realistic Rydberg laser excitation schemes is addressed within a Lindblad master equation, solved non-perturbatively, which allows us to calculate the full out-of-equilibrium steady-state phase diagram, and to search for novel ordered states which are stabilized by dissipation.