报告题目：Phases of quantum droplets in Bose-Einstein condensates

报告人：易俗研究员  中国科学院理论物理研究所

报告时间：2022年01月07日（周五）15：00

报告地点：理8栋一楼学术报告厅    邀请人：朱诗亮教授

报告内容：

        The recent experimental realization of quantum droplets in both dipolar gases and Bose mixtures is one of the major developments in ultracold atomic physics. Because these droplets emerge in the mean-field collapse regime with sufficiently large attractive inter-atomic interactions, they may represent a new state of matter in dilute atomic gases. For this system, the questions of primary importance are the stabilization mechanism and the quantum state of the droplets. A widely accepted theory for the droplet state is the extended Gross-Pitaevskii equation, which incorporate quantum fluctuation through Lee-Huang-Yang correction. This theory possesses an intrinsic flaw due to the imaginary Bogoliubov modes in the mean-field collapse regime, which invalidate the LHY correction.

        In this talk, I will present our results for the properties of the droplet states in three different systems. Here, we tackle the problem using the Gaussian-state theory which treats the quantum fluctuation in a self-consistent manner. We show that in addition to two new macroscopic squeezed states, we also find easily accessible criteria for the stabilization mechanism and the quantum state of the droplets. We believe that our work will clarify the misconceptions in current studies.

专家简介：

        易俗，中科院理论物理研究所研究员。1993年获中国科学技术大学学士学位，1996年获中国科学技术大学硕士学位，2002年获得美国Georgia Institute of Technology博士学位。2002.10-2006.1先后在美国Georgia Institute of Technology和Rice University从事博士后研究。2005年10月入选中科院“百人计划”，2010年获得国家“杰出青年基金”资助。主要从事和超冷原子物理相关的理论研究，已发表SCI论文近70篇，其中包括12篇《Physical Review Letters》。