Sundar Bhuvanesh, Gadway Bryce, Hazzard Kaden R A
Department of Physics and Astronomy, Rice University, Houston, TX, 77251, USA.
Rice Center for Quantum Materials, Rice University, Houston, TX, 77251, USA.
Sci Rep. 2018 Feb 21;8(1):3422. doi: 10.1038/s41598-018-21699-x.
Synthetic dimensions alter one of the most fundamental properties in nature, the dimension of space. They allow, for example, a real three-dimensional system to act as effectively four-dimensional. Driven by such possibilities, synthetic dimensions have been engineered in ongoing experiments with ultracold matter. We show that rotational states of ultracold molecules can be used as synthetic dimensions extending to many - potentially hundreds of - synthetic lattice sites. Microwaves coupling rotational states drive fully controllable synthetic inter-site tunnelings, enabling, for example, topological band structures. Interactions leads to even richer behavior: when molecules are frozen in a real space lattice with uniform synthetic tunnelings, dipole interactions cause the molecules to aggregate to a narrow strip in the synthetic direction beyond a critical interaction strength, resulting in a quantum string or a membrane, with an emergent condensate that lives on this string or membrane. All these phases can be detected using local measurements of rotational state populations.
合成维度改变了自然界中最基本的属性之一——空间维度。例如，它们能使一个实际的三维系统有效地表现为四维系统。受这些可能性的驱动，合成维度已在超冷物质的持续实验中得以构建。我们表明，超冷分子的转动状态可被用作延伸至许多（可能数百个）合成晶格位点的合成维度。耦合转动状态的微波驱动着完全可控的合成位点间隧穿，例如，可实现拓扑能带结构。相互作用会导致更为丰富的行为：当分子被冻结在具有均匀合成隧穿的实空间晶格中时，偶极相互作用会使分子在超过临界相互作用强度时，在合成方向上聚集形成一条窄带，从而产生量子弦或膜，并伴有出现在该弦或膜上的凝聚体。所有这些相都可通过对转动状态布居数的局部测量来检测。
