报告人：何院耀 　西北大学

时 间：2025年01月09日下午2:30

地 点：粤海校区致原楼1206室

报告摘要:

The  fermion paring and corresponding superconductivity and superfluidity are  of great interest in condensed matter physics. I will introduce our  several recent studies in this direction using auxiliary-field quantum  Monte Carlo (AFQMC) methods. In two dimensions (2D), it’s well known  that the superconductivity and superfluidity exhibits the BKT transition  at finite temperature. First, we have proposed a highly efficient  method to determine the BKT transition using the finite-size scaling of  condensate fraction, and applied this method to the 2D attractive  Hubbard model and 2D interacting Fermi gas. Second, we have studied the  pairing structure of the mixed-parity pairing in spin-orbit coupled 2D  attractive Hubbard model, concentrating on the spin-singlet and triplet  contributions to the pairing as well as the triplet pairing structure.  These two are performed with numerically exact AFQMC simulations. Third,  we have visisted the system of 2D attractive Hubbard model with  magnetic field with the constrained path approximation in AFQMC method.   which hosts the FFLO pairing. At mediate temperature, we have already  obtained signatures of the FFLO pairing which is well consistent with  the optical lattice experiments. All these calculations are expected to  serve as important benchmark and guideline for the corresponding ultracold atom experiments.

报告人简介:

何院耀，西北大学现代物理研究所教授、博士生导师。2013年6月，在南开大学凝聚态物理专业获理学学士学位，并入选国家首届“基础学科拔尖学生培养实验计划”；2018年6月在中国人民大学凝聚态物理专业获理学博士学位。2018年9月至2022年1月，在美国纽约Flatiron Institute，计算量子物理研究中心(CCQ)，任博士后研究员(Research Fellow)。2022年1月开始，在西北大学现代物理研究所工作，先后入选陕西省和国家青年人才项目。目前主要研究方向为凝聚态理论和强关联多体数值计算，包括量子蒙特卡洛算法的发展及其在格点模型、相互作用费米气体和关联电子材料等体系的应用，主要关注这些体系中量子磁性、超导超流性质、热力学和动力学性质的研究。目前已在Phy. Rev. Lett.，Phys. Rev. X和Phys. Rev. B等期刊发表学术论文20余篇，包括5篇PRL和4篇PRX，并在国内外学术会议上作邀请报告10余次，并多次在学术会议上讲授量子蒙特卡洛算法的教学报告。