Anderson Brandon M, Clark Logan W, Crawford Jennifer, Glatz Andreas, Aranson Igor S, Scherpelz Peter, Feng Lei, Chin Cheng, Levin K
James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA.
Phys Rev Lett. 2017 Jun 2;118(22):220401. doi: 10.1103/PhysRevLett.118.220401. Epub 2017 May 31.
We address band engineering in the presence of periodic driving by numerically shaking a lattice containing a bosonic condensate. By not restricting to simplified band structure models we are able to address arbitrary values of the shaking frequency, amplitude, and interaction strengths g. For "near-resonant" shaking frequencies with moderate g, a quantum phase transition to a finite momentum superfluid is obtained with Kibble-Zurek scaling and quantitative agreement with experiment. We use this successful calibration as a platform to support a more general investigation of the interplay between (one particle) Floquet theory and the effects associated with arbitrary g. Band crossings lead to superfluid destabilization, but where this occurs depends on g in a complicated fashion.
我们通过对包含玻色凝聚体的晶格进行数值振动来研究周期性驱动下的能带工程。由于不局限于简化的能带结构模型,我们能够处理振动频率、振幅和相互作用强度g的任意值。对于具有中等g值的“近共振”振动频率,通过基布尔-祖雷克标度得到了向有限动量超流体的量子相变,并与实验取得了定量一致。我们将这一成功的校准作为一个平台,以支持对(单粒子)弗洛凯理论与任意g相关效应之间相互作用的更全面研究。能带交叉会导致超流体失稳,但这种情况发生的位置以复杂的方式取决于g。