Lorentz skew scattering mechanism in nonlinear magneto-transport

Speaker

Prof. Shengyuan A. Yang

The Hong Kong Polytechnic University

Time

10：00am, June 11, 2026

Place

Material Science and Research Building B902

Prof. Shengyuan Yang earned his BSc from The University of Hong Kong (2005) and PhD from The University of Texas at Austin (2011). He served as an imaging geophysicist at CGG US Services in Houston from 2011 to 2013. In 2013, he joined Singapore University of Technology and Design (SUTD) as a founding member, progressing from Assistant Professor to tenured Associate Professor. From 2023 to 2025, he held a full Professorship at the University of Macau. In 2025, he joined The Hong Kong Polytechnic University. Prof. Yang’s research focuses on theoretical condensed matter physics. His work encompasses topological materials, 2D materials, transport theory, spintronics, valleytronics, and nonlinear responses.

Abstract

Nonlinear transport phenomena have been a focus of recent research. They unveil material properties that are inaccessible via linear responses, and they hold great potential for nonlinear electronics applications. Here, we unveil a new mechanism in nonlinear magneto-transport from cooperative action of Lorentz force and skew scattering. The significance of this Lorentz skew scattering mechanism lies in that it dominates both longitudinal and transverse nonlinear transport in highly conductive systems, and it exhibits a scaling behavior distinct from all known mechanisms. At low temperature, it shows a cubic scaling in linear conductivity, whereas the scaling becomes quartic at elevated temperature when phonon scattering kicks in. Applying our developed microscopic theory to surface transport in topological crystalline insulator SnTe and bulk transport in Weyl semimetals leads to significant results, suggesting a new route to achieve giant transport nonreciprocity in high-mobility materials with topological band features. Our theory has been confirmed in two recent experiments.