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非凡现象的关键因素。这些材料中的相互作用和无序是如何竞争或合作影响超导电性并产生新的量子态的，目前还不完全清楚。捕获在光学晶格中的超冷原子是由光形成的晶体，将作为模型系统来研究这一关键问题。光学散斑是由随机分布的亮区和暗区组成的一束激光，它的叠加将引入可控的、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。从这个系统中获得的知识可能会使人们更好地理解高温超导体，以及减轻无序对其性能影响的技术。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方面的尖端技术培训。该项目建立在之前的晶格实验的基础上，这些实验发现了使用RB-87原子的无序诱导玻色子绝缘体，并观察到了使用K-40原子的无序诱导的金属-绝缘体转变。将开展两个项目，旨在解决有关三个方面的强相互作用和无序的相互作用的未决问题。首先，浴对无序局域态的影响将使用捕获在自旋相关晶格中的RB-87超精细组分的混合物来测量。其次，利用捕获在无序光学晶格中的K-40原子的Rydberg修饰法研究了长程相互作用对量子局域化的影响。这些研究将推进无序量子气体的最新技术，从而使解决与凝聚态物理和材料科学相关的悬而未决问题的新方法成为可能，并增强对强关联系统的了解。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.