Quantum State Engineering with Bose-Einstein Condensates: Dressed-State and Hydrodynamic Approaches

玻色-爱因斯坦凝聚体的量子态工程：修饰态和流体动力学方法

• 批准号: 2207588
• 负责人: Peter Engels
• 金额: $ 58.91万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2207588&HistoricalAwards=false
• 关键词: Quantum; State; Engineering; Bose; Einstein

This project employs ultracold atomic gases to model complex quantum mechanical phenomena. Using laser cooling and related techniques, a cloud of atoms is cooled down to temperatures near absolute zero. Under appropriate conditions the atoms coalesce into a Bose-Einstein condensate, a macroscopic matter wave displaying quantum mechanical behavior. The large size of these objects, which can extend over hundreds of microns, implies that they are readily observable using custom imaging optics, and a rich toolset based on atomic physics is available for their manipulation. This, together with their quantum mechanical nature, makes them an ideal platform to study complex quantum mechanical phenomena. With the recent and ongoing development of novel experimental tools and theoretical approaches, such quantum analog modeling has become a major thrust of research in Atomic, Molecular and Optical (AMO) physics. Ultracold atom platforms can be applied to study phenomena from condensed matter physics, nonlinear science, hydrodynamics, quantum optics, and more, demonstrating their importance as highly versatile testbeds in modern physics. The experiments conducted in this project investigate several approaches to probe the emergence of periodic structures with crystal-like properties from the macroscopic matter wave of a Bose-Einstein condensate. The dynamical properties of such crystalline structures pose many theoretical challenges, and the experiments provide essential benchmark data for the development of a theoretical understanding. Going beyond the realm of ultracold atoms, the insight gained through this line of research is of high relevance for condensed matter physics and nonlinear science as well. The experiments are conducted with complex setups that utilize a large range of modern experimental techniques, including lasers and optics, ultrahigh vacuum technology, automation programming, and advanced electronics. This makes them ideal platforms to train students in a multitude of areas relevant for modern quantum technologies which use quantum mechanical effects in sensor applications e.g. to detect magnetic, electric or gravitational fields, for fundamentally secure communication, or to establish new paradigms for efficient computing. This research program advocates the use of ultracold atomic gases as a highly flexible platform for the study of quantum phases and dynamics. Along the lines of quantum analog simulation, several innovative approaches to investigate emerging band structures and associated phenomena in dilute-gas Bose-Einstein condensates (BECs) are employed. The starting point is a BEC in which spin and motional degrees of freedom are coupled by a set of Raman laser beams. This spin-orbit coupling is then supplemented with a radiofrequency dressing or microwave dressing to generate effective lattice structures with unusual properties. In the first case, an effective Zeeman lattice emerges even though neither the spin-orbit coupling nor the radiofrequency alone produce a periodic band structure. The second case leads to a new method to generate a supersolid-like state with large spatial periodicity, overcoming the limitations of previous approaches. As a third, complementary approach coming from a quantum hydrodynamics perspective, the experimental realization of densely packed interacting soliton trains provides a very different and unexplored access to the study of crystalline properties that arise in a superfluid system without imposing a periodic external potential. The quantum analog simulation of condensed matter, hydrodynamic or nonlinear phenomena using the versatile toolbox of atomic physics is a highly active area in quantum gas research, and the experiments provide important benchmark data motivating the concurrent development of theoretical approaches.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.

该项目使用超冷原子气体来模拟复杂的量子力学现象。利用激光冷却和相关技术，原子云被冷却到接近绝对零度的温度。在适当的条件下，原子凝聚成玻色-爱因斯坦凝聚体，这是一种显示量子力学行为的宏观物质波。这些物体的大小可以延伸到数百微米以上，这意味着使用定制的成像光学装置很容易观察到它们，并且可以使用基于原子物理的丰富工具集来操纵它们。这一点，加上它们的量子力学性质，使它们成为研究复杂量子力学现象的理想平台。随着新的实验工具和理论方法的不断发展，这种量子模拟模型已经成为原子、分子和光学(AMO)物理研究的主要方向。超冷原子平台可用于研究凝聚态物理、非线性科学、流体力学、量子光学等现象，显示出它们在现代物理中作为高度通用的试验台的重要性。在这个项目中进行的实验研究了几种从玻色-爱因斯坦凝聚体的宏观物质波中探索具有晶体性质的周期结构出现的方法。这种晶体结构的动力学性质提出了许多理论挑战，这些实验为发展理论理解提供了必要的基准数据。超越了超冷原子的领域，通过这一系列研究获得的洞察力对凝聚态物理和非线性科学都具有高度的相关性。这些实验是在复杂的装置中进行的，这些装置利用了广泛的现代实验技术，包括激光和光学、超高真空技术、自动化编程和先进电子学。这使它们成为培训学生在与现代量子技术相关的众多领域的理想平台，现代量子技术在传感器应用中使用量子力学效应，例如检测磁场、电场或引力场，从根本上确保通信安全，或建立高效计算的新范式。这项研究计划提倡使用超冷原子气体作为研究量子相和动力学的高度灵活的平台。沿着量子模拟的思路，采用了几种创新的方法来研究稀薄气体玻色-爱因斯坦凝聚体(BEC)中出现的能带结构和相关现象。起始点是BEC，其中自旋和运动自由度由一组拉曼激光束耦合。然后，这种自旋-轨道耦合被射频修整或微波修整补充，以产生具有特殊性质的有效晶格结构。在第一种情况下，即使自旋-轨道耦合和射频本身都不会产生周期性的能带结构，也会出现有效的塞曼晶格。第二种情况导致了一种新的方法来产生具有大空间周期性的类超固体状态，克服了以前方法的局限性。作为第三种从量子流体力学角度出发的补充方法，密集堆积相互作用孤子串的实验实现提供了一种非常不同和未经探索的途径，可以在不施加周期外势的情况下研究超流体系统中出现的晶体性质。使用原子物理的通用工具箱对凝聚态、流体力学或非线性现象进行量子模拟是量子气体研究中一个非常活跃的领域，这些实验提供了重要的基准数据，推动了理论方法的同时发展。该奖项反映了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。