Understanding Quantum Non-Equilibrium Matter: Many-Body Localisation versus Glasses, Theory and Experiment

了解量子非平衡物质：多体定位与眼镜、理论和实验

基本信息

批准号：
EP/R04421X/1
负责人：
Juan Garrahan
金额：
$ 61.82万
依托单位：
University of Nottingham
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2018
资助国家：
英国
起止时间：
2018 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FR04421X%2F1
关键词：
Understanding Quantum Non Equilibrium Matter

项目摘要

Many-body systems comprise everything from simple metals, over complicated organic molecules, all the way to living cells. While their physics can be extremely complex, this complexity is however often mostly irrelevant, as most such systems will - when left alone - thermalise, a process through which most information about their preparation history and their initial state is lost. Think of pouring milk into your coffee or tea: there are many different important individual details describing this process - how fast, how much milk, angle and position of milk jug, milk temperature, and so on. All of those parameters are needed to predict the intricate turbulent pattern seen when one starts stirring the tea. At long time, however, all this complexity is hidden and we see merely a homogeneous brownish liquid. This behaviour is typical of ergodic systems and central to statistical mechanics; it allows us to make concrete predictions about a system given only a handful of parameters such as total energy. Physics knows, however, about exceptions to this behaviour. In particular, in recent years, the phenomenon of many-body localisation (MBL) has emerged as a new paradigm for the absence of thermalisation and non-ergodicity in interacting quantum systems. In these systems, all degrees of freedom become localised by an external disorder, and are therefore partially decoupled from each other and cease to thermalise. In particular, it could be shown that these systems keep a much better local memory of their initial conditions. This peculiar effect might for instance be exploited in the future to design better materials to host quantum bits with reduced decoherence - even if some information leaks into the local environment, it will remain local for much longer. While MBL is a novel quantum effect, in classical systems the paradigm of slow dynamics and non-ergodicity is the glass transition, whereby fluid systems - such as liquids, colloidal suspensions or even granular mixtures - cease to flow and fall out of equilibrium at low temperatures or high densities. Here, we seek support for a new theory-experiment collaboration between Nottingham and Cambridge aimed at developing a fundamental understanding of central aspects of non-equilibrium quantum many-body systems. In particular, we propose to establish the connections between MBL and glasses, thereby unveiling new mechanisms for quantum slow relaxation and non-ergodicity, with potential implications for the design and control of novel quantum non-equilibrium materials and devices. Our team comprises researchers with ample experience in experimental and theoretical atomic physics, statistical physics and condensed matter, who have made central contributions to MBL, glasses, open quantum systems, and other topics directly related to this proposal. This joint project will allow us to work hand-in-hand such that new theoretical ideas can quickly be tested in the experiment, which directly feeds back into theoretical developments.