Key Laboratory of Inorganic Functional Material and Device, CAS, Shanghai Institute of Ceramics, Chinese Academy of Sciences
中国科学院无机功能材料与器件重点实验室

Topological Vortex Domains in Quantum Materials

Prof. Sang-W. Cheong

Center for Quantum Materials Synthesis and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA,

时间：2017年12月06日（星期三）上午10:00

　　地点： 4 号楼 14楼第一会议室

联系人：李国荣、武安华研究员

欢迎各位老师同学光临!

Charge/spin/orbital order in quantum materials accompanies directional variants and translational variants. The large-range domain wall configuration of these variants can be associated with non-trivial topologies and topological vortex defects. In addition, the temporal evolution of the domain wall configuration and topological vortices or their changes with external stimuli can strictly follow topological charge conservation laws. We also found that if the relevant phase transition is continuous, the formation kinetics of topological vortices follows the so-called Kibble-Zurek mechanism, which is important to understand the early stage of universe after big bang. Thus, a tiny single crystal of quantum materials can be a test bed for the development of this cosmos. Statistical analysis of the spatial distribution of vortex domains in certain compounds unveils a power law, which resembles the effect of “the rich get richer”. We will discuss a number of intriguing exemplary cases in compounds such as multiferroic R(Mn,Fe)O₃, hybrid improper ferroelectric (Ca,Sr)₃Ti₂O₇ and antiferromagnetic-superconducting Sr₂VO₃FeAs.