Quantum Monte Carlo studies of emerging quantum phases and quantum phase transitions in frustrated quantum magnets

本提案的目标是利用无偏大尺度量子蒙特卡罗模拟来研究受挫量子自旋系统。所考虑的模型是通过将量子涨落引入受挫的经典自旋模型而产生的，并且在数值计算中不受量子蒙特卡罗符号问题的影响。几何挫折的影响，强量子涨落和无序在这样的系统将被研究，特别是新兴的量子相和量子相变的性质。我们开发的量子蒙特卡罗方法既可以用于计算基态，也可以用于计算有限温度性质。系统的尺寸实现了对热力学极限的可靠分析。

The goal of this proposal is to study frustrated quantum spin systems using unbiased largescale quantum Monte-Carlo simulations. The models under consideration arise from introducing quantum fluctuations to frustrated classical spin models, and do not suffer from a quantum Monte Carlo sign problem in the numerical calculations. The effects of geometric frustration, strong quantum fluctuations and disorder in such systems will be studied, in particular the nature of emerging quantum phases and quantum phase transitions. The quantum Monte Carlo methods we developed can be used for the calculation of both ground state as well as finite temperature properties. The systems sizes achieved allow for a reliable analysis to the thermodynamic limit.