PDF《induced by periodic driving》

武汉物数所理论交叉学术交流系列报告 主办单位:武汉物数所理论与交叉研究部 Nonequilibrium quantum phase transition induced by periodic driving 安钧鸿 教授 兰州大学 2019年6月6日(周四) 下午15:00 新波谱楼M10楼1016-17报告厅 报告人简介: 安钧鸿,教授,博士生导师.

2005年在兰州大学 获得博士学位并留校工作.2006年至2014年12月相继 在台湾成功大学和新加坡国立大学开展博士后和合作 科研.2013年入选教育部新世纪优秀人才支持计划;

2016年入选甘肃省飞天学者;

2017年入选中央军委科 技委主题专家组专家;

2018年入选中国物理学会量子 光学专业委员会委员;

2019年入选国家"万人计划" 青年拔尖人才.主要从事量子物理基础问题研究,包 括量子光学、量子信息、量子相变以及非平衡量子统 计动力学等方面的研究.主持在研/完成国家自然科 学基金5项;

教育部博士点基金和甘肃省自然科学基 金各1项. Abstract: Periodic driving has become one highly versatile tool in quantum control. Many efforts have been devoted to explore non-trivial effects induced by periodic driving on quantum systems. In this talk, I will report that interesting nonequilibrium quantum phase transitions (QPTs) can be triggered by engineering non-trivial band- gap structure and midgap bound state in Floquet quasi-energy spectrum using periodic driving. I will clarify this idea by two examples. One is to induce more colorful topological QPT in one-dimensional Kitaev model and in two-dimensional Haldane model by periodic driving. A tunable number of topologically protected Majorana edge modes can be generated in Kitaev model by a well-designed periodic driving, which may supply a novel way to identify the topological phase of the system. The topological insulator phases with a large Chern number can be triggered in the Haldane model by periodic driving. A proposal for such large- topological-number phases realized in cold-atom systems is given. Another is to induce nonequilibrium QPT in the system consisting of a spin interacting with a spin bath by periodic driving. It is found that whenever the QPT manifested by the formation of a midgap state in the Floquet quasienergy spectrum occurs, the decoherence of the spin induced by the spin bath can be suppressed. This opens an avenue to control decoherence by periodic driving. (第二一三期)