Probing Non-Equilibrium Quantum Many-Body Dynamics with Bright Matter-Wave Solitons

用亮物质波孤子探测非平衡量子多体动力学

基本信息

批准号：
EP/L010844/1
负责人：
Simon Cornish
金额：
$ 97.95万
依托单位：
Durham University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2014
资助国家：
英国
起止时间：
2014 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FL010844%2F1
关键词：
Probing Non Equilibrium Quantum Many

项目摘要

Dilute gases of alkali atoms are now routinely cooled to within a millionth of a degree of absolute zero using laser light, permitting them to be confined in traps formed due to the interaction of the atom with either an applied magnetic field or a far-detuned off-resonant laser beam. Further cooling by evaporation in such traps leads, in the case of bosonic atoms, to the creation of a new state of matter, known as a Bose-Einstein condensate, in which the quantum mechanical nature of the particles dominates over their classical behaviour. Such condensates are often viewed as the atomic or matter-wave equivalent of coherent laser light.Since their first observation in 1995, Bose-Einstein condensates have been used with great success to investigate a vast range of physical phenomena from fundamental studies of superfluidity to strongly correlated many-body states in optical lattices, providing insight into more complicated condensed matter systems. This success stems from two important features of ultracold quantum gases. Firstly, from an experimental stand-point, ultracold atomic gases are readily manipulated and controlled with external electromagnetic fields (dc, radio-frequency, microwave and optical) permitting a very high degree of real-time flexibility in the experimental configuration and highly sensitive detection. Secondly, Bose-Einstein condensates have proved theoretically tractable, due largely to their dilute, weakly interacting nature, leading to a deeper understanding of experimental observations. This makes ultracold quantum gases an ideal testing ground for the cutting-edge developments in our theoretical understanding of the behaviour of many-body quantum systems.Here, we propose a program of fundamental research intended to yield a better general understanding of the dynamics of non-equilibrium interacting quantum many-body systems, using atomic Bose-Einstein condensates of 85Rb. Specifically, we will exploit a collision resonance (known as a Feshbach resonance) between two 85Rb atoms to tune the atomic interactions in the condensate to be attractive, thereby generating bright matter-wave solitons; robust, non-dispersive atomic wave-packets confined to propagate in one dimension, in which the attractive atomic interactions exactly compensate the usual dispersion. Solitons arise as solutions to nonlinear partial differential equations describing a diverse range of physical systems. First observed in the shallow water of the Union Canal in Scotland in 1834, solitons have since been studied in many other contexts, including nonlinear optics, biophysics, astrophysics and particle physics. In the atomic context, the underlying quantum nature of the system provokes sophisticated many-body quantum treatments to accurately capture the essential physics. This proposal describes a systematic, closely interlinked experimental-theoretical study of such "quantum" bright matter-wave solitons with a view to exposing the coherence and entanglement properties of bright solitons, whilst developing new advanced theoretical treatments applicable to other quantum many-body systems. Working together with the leading international experts in the field, we aim ultimately to assess the feasibility of using quantum bright solitons to generate Schrödinger cat states for quantum-enhanced interferometry. The proposed research falls within the remit of two of the identified current Grand Challenges in Physics, "Emergence and Physics Far From Equilibrium" and "Quantum Physics for New Quantum Technologies", and thereby contributes to UK science in areas where there is recognised potential for significant societal and economic impact.

现在，通常使用激光将碱原子的稀释气体冷却到绝对零度的百万分之一以内，从而使它们能够被限制在由于原子与施加的磁场或远失谐的相互作用而形成的陷阱中。 - 共振激光束。在玻色原子的情况下，通过在这种陷阱中蒸发进一步冷却会产生一种新的物质状态，称为玻色-爱因斯坦凝聚态，其中粒子的量子力学性质支配着它们的经典行为。这种凝聚体通常被视为相干激光的原子或物质波等效物。自 1995 年首次观察以来，玻色-爱因斯坦凝聚体已被成功地用于研究粒子。从超流性的基础研究到光学晶格中强相关的多体态的广泛物理现象，提供了对更复杂的凝聚态物质系统的洞察，这一成功源于超冷量子的两个重要特征。首先，从实验的角度来看，超冷原子气体很容易通过外部电磁场（直流、射频、微波和光学）进行操纵和控制，从而允许实验配置具有非常高的实时灵活性和高度的灵活性。其次，玻色-爱因斯坦凝聚体在理论上已被证明是易于处理的，这主要是由于其稀释的、弱相互作用的性质，从而使人们对实验观察有了更深入的了解，这使得超冷量子气体成为理想的试验场。表彰我们对多体量子系统行为的理论理解的前沿发展。在这里，我们提出了一项基础研究计划，旨在更好地了解非平衡相互作用的量子多体系统的动力学，具体来说，我们将利用两个 85Rb 原子之间的碰撞共振（称为费什巴赫共振）来调整凝聚体中的原子相互作用，使其具有吸引力，从而产生明亮的光。物质波孤子；局限于一维传播的鲁棒、非色散原子波包，其中有吸引力的原子相互作用精确地补偿了通常的色散，作为描述各种物理系统的非线性偏微分方程的解。 1834 年，孤子首次在苏格兰联合运河的浅水中被观察到，此后人们在许多其他领域进行了研究，包括非线性光学、生物物理学、天体物理学和粒子物理学。在原子背景下，系统的潜在量子性质引发了复杂的多体量子处理，以准确捕获基本物理原理。该提案描述了对这种“量子”亮物质波孤子进行系统的、紧密相连的实验理论研究。为了揭示亮孤子的相干性和纠缠特性，同时开发适用于其他量子多体系统的新的先进理论处理方法，我们与该领域的领先国际专家合作，最终目标是评估使用量子亮孤子的可行性。到生成用于量子增强干涉测量的薛定谔猫态，该研究属于当前物理学中两个重大挑战的范围，即“远离平衡的出现和物理学”和“新量子技术的量子物理学”。英国科学领域被认为具有重大社会和经济影响的潜力。