报告题目:Precision many-body physics by computation

报  告  人:Shiwei Zhang, College of William and Mary, Williamsburg, Virginia, USA

报告时间:2018-01-04 16:00

报告地点:理科楼郑裕彤讲堂

报告摘要:The physics of many-electron systems remains one of the great challenges in modern physics. Experimental progress in condensed matter and with ultracold atoms offer exciting new opportunities. Recently, rapid progress has also been achieved with computational approaches. This brings new synergy for advancing our understanding of correlated electron systems. I will describe our work to develop one of the computational frameworks, the auxiliary-field quantum Monte Carlo (AFQMC), and to determine the ground-state properties of two fundamental two-dimensional systems: the Fermi gas and the repulsive Hubbard model. In the Fermi gas, where the interaction is attractive, exact computations are performed under experimental conditions with ultracold atoms, and the interplay between superfluidity and Rashba spin-orbit coupling is investigated. In the repulsive Hubbard model, the magnetic and charge orders upon doping are examined and several key questions are answered in the context of high-termerature superconductivity. We will conclude with brief comments on the general prospect of ab initio quantum many-body computations in molecules and materials.