主讲人：易俗 研究员（中国科学院理论物理研究所）

题目：Phases of quantum droplets in Bose-Einstein condensates

时间：2021年04月26日上午09：00

地点：理工楼1226

联系人：黄亮

报告摘要：

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.

个人简介：

易俗，中国科学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年10月至2006年1月期间先后在美国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。主要从事与超冷原子物理相关的理论研究，在相关领域发表SCI论文60余篇，包括12篇PRL，引用2000余次。