题目：3D Quantum Hall effect

报告人：卢海舟 Hai-Zhou Lu

   SouthernUniversity of Science and Technology of China

地点： 教十二-201

时间： 3月15日，周五，15:00-17:00

Abstract

The discoveries of the quantum Hall effect have led to three Nobelprizes and the booming field of topological states of quantum matter. So far, the quantum Hall effect is observed only in 2D systems. We show that theFermi arcs can give rise to a distinctive quantum Hall effect in topologicalsemimetals in three dimensions [1]. Topologicalsemimetals are 3D topological states of matter, in which the energy bands touchat a finite number of Weyl nodes. They host topologically-protected surfacestates, known as the Fermi arcs. Via a “wormhole” tunnellingassisted by the Weyl nodes, the Fermi arcs at two opposite surfaces can form a single2D electron gas and support a quantum Hall effect in three dimensions. Possiblesignatures of the 3D quantum Hall effect have been observed in severalexperiments on the topological Dirac semimetal Cd3As2 [2-5]. Our discovery of this 3D quantum Hall give anexample of (d-2)-dimensional boundary states, a promising direction intopological states of quantum matter.

References:

[1] C. M. Wang, Hai-Peng Sun, Hai-Zhou Lu*, and X. C. Xie, Phys. Rev. Lett. 119,136806 (2017).

[2] C. Zhang, F. X. Xiu, et al., Nature Comm. 8, 1272 (2017); Nature 565, 331 (2019).

[3] Uchida, et al., Nature Comm. 8, 2274 (2017).

[4] Schumann, Stemmer, et al., Phys. Rev. Lett. 120, 016801 (2018).

[5] Lin, Z. M. Liao, et al., Phys. Rev. Lett. 112, 036602 (2019)].

Short Biography

Haizhou Lu obtained his Ph.D. in Physics from Institute for AdvancedStudy, Tsinghua University, Beijing, in 2007. From 2007 to 2015, he was a Postdocand then Research Assistant Professor at the University of Hong Kong. He is nowa Professor of physics at Southern University of Science and Technology,Shenzhen. His research is on the quantum transport in topological states ofmatter. He has published over 70 articles in physics journals, including 13 inPRL, 1 in Nature Physics, 4 in Nature Communications, 2 in Nature, with a citation over 3000 and h-index of 28.