Bath-Induced and Long-Range Interactions in Disordered Strongly Correlated Optical Lattices

无序是自然界中不可避免的，它可以强烈地影响支撑现代技术的材料的行为。物理学面临的一个紧迫问题是理解量子材料中无序和强粒子间相互作用的相互作用。强相互作用是高温超导等显著现象的关键因素。相互作用和无序如何在这些材料中竞争或合作来影响超导性并产生新的量子态尚不完全清楚。光学晶格是一种由光形成的晶体，被捕获的超冷原子将被用作研究这一关键问题的模型系统。光学散斑是由随机分布的亮区和暗区组成的激光束，叠加光学散斑将引入可控的、完全表征的无序。当无序和相互作用被独立调谐时，不同量子态的出现将被测量。从该系统中获得的知识可能会导致对高温超导体和减轻无序对其性能影响的技术的更好理解。下一代工程师和科学家将接受激光科学、高频微波电子学和高速计算机控制信号等尖端技术的培训。该项目建立在先前的晶格实验的基础上，该实验使用Rb-87原子发现了一个无序诱导的玻色子绝缘体，并使用K-40原子观察了一个无序诱导的金属-绝缘体转变。两个项目旨在解决有关强相互作用和三维无序的相互作用的悬而未决的问题。首先，将使用捕获在自旋依赖晶格中的Rb-87超细组分的混合物来测量槽对无序局域态的影响。其次，利用里德伯修饰无序光学晶格中的K-40原子，研究远程相互作用对量子局域化的影响。这些研究将推动无序量子气体的最新发展，从而为解决与凝聚态物理和材料科学相关的悬而未决的问题提供新的方法，并增强对强相关系统的认识。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Disorder, inescapable in nature, can strongly affect the behavior of materials underpinning modern technologies. An urgent problem confronting physics is understanding the interplay of disorder and strong inter-particle interactions in quantum materials. Strong interactions are an ingredient crucial to remarkable phenomena such as high-temperature superconductivity. How interactions and disorder compete or cooperate in these materials to affect superconductivity and give rise to new quantum states is not fully understood. Ultracold atoms trapped in an optical lattice, which is a crystal formed from light, will be used as a model system to study this critical problem. Controllable and completely characterized disorder will be introduced by superimposing optical speckle, which is a laser beam consisting of randomly distributed bright and dark regions. The emergence of different quantum states as the disorder and interactions are independently tuned will be measured. Knowledge gained from this system may lead to a better understanding of high-temperature superconductors and techniques for mitigating the impact of disorder on their performance. The next generation of engineers and scientists will be trained on cutting-edge technologies in laser science, high-frequency microwave electronics, and high-speed computer-controlled signaling.This project builds on previous lattice experiments that discovered a disorder-induced bosonic insulator using Rb-87 atoms and observed a disorder-induced metal-insulator transition using K-40 atoms. Two projects designed to resolve outstanding questions regarding the interplay of strong interactions and disorder in three dimensions will be pursued. First, the impact of a bath on disorder-localized states will be measured using a mixture of Rb-87 hyperfine components trapped in a spin-dependent lattice. Second, the influence of long-range interactions on quantum localization will be investigated using Rydberg dressing of K-40 atoms trapped in a disordered optical lattice. These studies will advance the state-of-the-art in disordered quantum gases, thus enabling new methods for attacking outstanding questions related to condensed matter physics and materials science and enhancing knowledge of strongly correlated systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.