Time: June 7th, 14:00
Tencent Meeting: https://meeting.tencent.com/dm/iRFlDtVVCpQc
Meeting ID: 477-318-662
Host: Prof. Qing Dai
Title: Bianisotropy induced transverse-spin and anomalous tunneling
Speaker: Shuang Zhang, University of Hong Kong, http://hub.hku.hk/cris/rp/rp02759
Metamaterials are artificially engineered structures that exhibit unconventional electromagnetic properties that go beyond what can be obtained from nature, such as negative refraction, gigantic chirality and bianisotropy. Bianisotropy refers to coupling of electric and magnetic responses along orthogonal directions, and it underlies many interesting phenomena such as topological protection and asymmetric reflection. In this talk I will present two interesting phenomena associated with biansotropy: transverse spin of bulk optical waves and anomalous tunneling. By engineering the complex electromagnetic responses of metamaterials, we show that a bulk optical wave can possess transverse spin, while previously optical transverse spin had only been discovered for evanescent waves close to an interface. With combination of bianisotropy and zero-refractive-index, we discover that an incident electromagnetic wave can be manipulated to experience anomalous tunneling accompanied by a growing electric or magnetic field. These observations greatly enrich our understanding of propagation and tunneling of waves in electromagnetic systems.
Shuang Zhang is a chair Professor in the Department of Physics and the Department of Electronic & Electrical Engineering at the University of Hong Kong. He obtained his PhD in Electrical Engineering from the University of New Mexico. Thereafter he worked as postdoc at UIUC and UC Berkeley. He joined the University of Birmingham, UK as a Reader in 2010 and was promoted to professor in 2013. Prof. Zhang joined the University of Hong Kong in 2020. Shuang Zhang has published over 200 research papers in journals including Nature, Science, NPG journals, Physical Review Letters. He was the recipient of IUPAP award in Optics (2010), ERC consolidator grant (2015-2020), Royal Society Wolfson Research Award (2016-2021), and was elected OSA fellow in 2016, and has been on the list of highly cited researchers (by Clarviate) since 2018.
You are all welcome!