Action-based quantum Monte Carlo approach to fermion-boson lattice models

基于动作的费米子-玻色子晶格模型的量子蒙特卡罗方法

• 批准号: 229508950
• 负责人: Dr. Martin Hohenadler
• 金额: --
• 依托单位: Institut für Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/229508950?language=en
• 关键词: Action; based; quantum; Monte; Carlo

By extending the continuous-time quantum Monte Carlo method, this project aims at understanding fundamental effects in models describing the interaction of fermionic charge carriers with bosonic degrees of freedom such as phonons or magnons. The models of interest here capture electronic correlations and quantum fluctuations, and pose a challenge even to state of the art numerical methods. The action-based path-integral formulation of the continuous-time quantum Monte Carlo method permits to include general, nonlocal two-particle interactions mediated by bosons. Important aspects to be addressed include the Peierls transition, polaron formation, the competition between charge-density-wave order and superconductivity, soliton excitations in polymers, and the role of spin fluctuations for electronic pairing.

通过扩展连续时间量子蒙特卡罗方法，本项目旨在理解描述费米子载流子与玻色子自由度（如声子或磁振子）相互作用的模型中的基本效应。这里感兴趣的模型捕获了电子相关性和量子涨落，甚至对最先进的数值方法提出了挑战。连续时间量子蒙特卡罗方法的基于作用的路径积分公式允许包括一般的，由玻色子介导的非局部两粒子相互作用。需要解决的重要方面包括佩尔斯跃迁，极化子形成，电荷密度波序和超导性之间的竞争，聚合物中的孤子激发，以及电子配对中自旋涨落的作用。