Dynamics, disorder and noise in quantum spin liquids

最近在量子自旋液体行为候选材料的生长和表征方面的实验进展，使人们能够前所未有地控制和理解无序的作用。由此产生的现象是令人兴奋的多样化，包括局部化和玻璃性，拓扑激发的散射，以及非克莱默离子中有效量子涨落的可调性。我们计划在理论上研究这些效应，借助经典等效系统的蒙特卡罗模拟，以及量子玩具模型的精确对角化和有效的分析方法。我们对了解这些系统中的弛豫和响应过程特别感兴趣，并对其磁噪声进行预测，例如可以通过最先进的超快光谱或SQUID测量进行实验。

Recent experimental advances in growth and characterisation of candidate materials for quantum spin liquid behaviour have brought to the fore an unprecedented ability to control and understand the role of disorder. The resulting phenomenology is excitingly varied, including instances of localisation and glassiness, scattering of topological excitations, and tunability of effective quantum fluctuations in non-Kramer ions. We plan to study these effects theoretically, with the help of Monte Carlo simulations of classical equivalent systems, as well as exact diagonalisation of quantum toy models, and effective analytical approaches. We are particularly interested in understanding the relaxation and response processes in these systems, and in making predictions for example on their magnetic noise that may be accessed experimentally in state of the art ultrafast spectroscopy or SQUID measurements.