时间：2016年11月10日上午9:30

地点：下沙校区D楼204会议厅

摘要：

  In this talk, we will introduce fully new applications of photon’s orbital angular momentum in quantum simulation of topological physics. The basic idea is to design a degenerate cavity supporting photonic modes carrying different orbital angular momentum (i.e. the Laguerre-Gaussian modes), whose resonance frequencies are the same. By coupling photons in different orbital angular momentum states, a single degenerate cavity is equivalent to a 1D coupled-cavity array. Consequently, 1D coupled degenerate cavity array can be used to simulate 2D physics. We proposed some schemes to realize arbitrary Abelian gauge field, SU(2) non-Abelian gauge field, to detect topological invariants such as edge state and Chern number, and to observe topological quantum phase transition. In contrast to other 2D proposals, this 1D structure greatly reduces the complexity of the simulator, and feasible scale of simulation is also increased. Furthermore, we also investigate 1D topological models by using single degenerate cavity. By designing the boundary of such kind of synthetic dimension, we may observe the dynamics of edge modes which will exhibit topological phase transition of models. By manipulating the synthetic dimension in the degenerate cavity, some significant all-optical devices can be constructed.

报告人简介：

  周正威， 中国科学技术大学物理学院教授，中国科学技术大学光学与光学工程系执行主任。分别在中国科学技术大学获得学士学位和博士学位。2005年，获教育部“新世纪优秀人才支持计划”的资助；2007年, 获安徽省第五届自然科学优秀学术论文一等奖；2008年, 获中科院卢嘉锡青年人才奖。迄今为止，发表SCI论文80多篇（包括Nature Photonics 1篇, Nature Communications 1篇, PRL 3篇, PRA、B 41篇），被SCI他人引用近1000次，H-index为15。目前的研究兴趣主要集中在：量子模拟与量子调控、多体纠缠和量子相变等。