Seminar by Professor Quansheng WU (Institute of Physics, CAS)

In this talk, we will introduce a nonperturbative first-principles methodology under magnetic fields, combined with semiclassical Boltzmann transport theory, to quantitatively compute magnetoresistance and the Hall effect in real materials. We discuss the unsaturated magnetoresistance observed in both top ologically trivial and nontrivial systems, revealing the critical roles of carrier compensation, open-orbit mechanisms, and Fermi-surface topology. Our theoretical predictions exhibit excellent agreement with low-temperature experimental data for prototypical metals, semimetals, Weyl semimetals, and magnetic materials. For the first time, we propose a scaling law governing Hall resistivity as a function of temperature and magnetic field. This new approach successfully explains the complex magnetoresistance and Hall-effect behaviors found in magnetic materials, aligning closely with experimental observations and underscoring the decisive influence of Fermi-surface geometry and the Lorentz force on magnetic transport properties. We also demonstrate that, under magnetic fields, the characteristic ρ–T curve no longer serves as a reliable criterion for distinguishing metals, semiconductors, or insulators. Our work provides a novel theoretical framework for understanding magnetic transport phenomena and introduces the WannierTools software for electronic-structure analysis, thereby opening new pathways for characterizing electronic structures.

You may also like the following events from Department of Physics, CUHK 香港中文大學物理系:

• This Tuesday, 17th June, 02:00 pm, Seminar by Dr. Wuhao CHEN (Quantum Science Center of Guangdong-Hongkong-Macao Greater Bay Area (Gua in Hong Kong
• This Friday, 20th June, 10:00 am, Seminar by Dr. Zhuo CAO (Forschungszentrum Jülich GmbH) in Hong Kong

Also check out other Workshops in Hong Kong.