论文标题
光学晶格的第二个Bloch带中玻色子的轨道多体动力学
Orbital many-body dynamics of bosons in the second Bloch band of an optical lattice
论文作者
论文摘要
rubidium原子的Bose-Einstein冷凝物（BEC）是在光学方形晶格的第二个Bloch带中的两个变性能量最小值中制备的。观察到了两个能量最小值之间的BEC的随后振荡，这是由两个不同的碰撞过程驱动的：常规的哈伯德型现场碰撞和改变轨道风味的碰撞过程。这些碰撞相互作用的相对强度的振荡频率尺度可以通过单位电池的实验控制良好的失真来轻松调节。将观测结果与两个单粒子模式的量子模型和晶格12x12管状位点的半经典多波段紧密结合模拟进行了比较。这两个模型都重现了观察到的振荡量子多体动力学，并显示了振荡频率对现场和变化碰撞过程强度之间比率的正确依赖性。
A Bose-Einstein condensate (BEC) of rubidium atoms is prepared in one of two degenerate energy minima in the second Bloch band of an optical square lattice. A subsequent oscillation of the BEC between the two energy minima is observed, which is driven by two distinct collision processes: the conventional Hubbard-type on-site collision and a collision process that changes the orbital flavor. The oscillation frequency scales with the relative strength of these collisional interactions, which can be readily tuned via an experimentally well controlled distortion of the unit cell. The observations are compared to a quantum model of two single-particle modes and to a semi-classical multi-band tight-binding simulation of 12x12 tubular sites of the lattice. Both models reproduce the observed oscillatory quantum many-body dynamics and show the correct dependence of the oscillation frequency on the ratio between the strengths of the on-site and flavor-changing collision processes.
