演講公告

演講主題：Ground State Patterns and Phase Transitions of Spin-1 Bose-Einstein Condensates via $\Gamma$-Convergence Theory
主講人：謝天長博士 (理論中心)
演講日期：2017年3月7日(星期二) 下午2:00 –3:00
演講地點：(光復校區) 科學一館223室
茶會時間：當天下午1:30 (科學一館205室)
摘要內容：
In this talk, I will introduce an analytic theory for the ground state patterns and their phase transitions for spin-1 Bose-Einstein condensates on a bounded domain in the presence of a uniform magnetic field. Within the Thomas-Fermi approximation, these ground state patterns are composed of four basic states: magnetic state, nematic state, two-component state and three-component state, separated by interfaces. A complete phase diagram of the ground state patterns are found analytically with different quadratic Zeeman energy $q$ and total magnetization $M$ for both ferromagnetic and antiferromagnetic systems. Using the $\Gamma$-convergence technique, it is found that the semi-classical limits of these ground states minimize an energy functional which consists of interior interface energy plus a boundary contact energy. As a consequence, the interface between two different basic states has constant mean curvature, and the contact angle between the interface and the boundary obeys Young's relation.
相關檔案：Talk_1060307.pdf

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