Speaker's Brief Introduction：Professor Liyuan Zhang received his Ph.D. in physics from the Georgia Institute of Technology in 2007. After completing his doctoral studies, he held postdoctoral positions at Purdue University, Brookhaven National Laboratory, and Stony Brook University. In 2012, he was selected for the second cohort of China’s Young Thousand Talents Program and joined the Department of Physics at Renmin University of China as an Associate Professor. Since 2014, he has been with the Department of Physics, College of Science, Southern University of Science and Technology (SUSTech), where he was promoted to full Professor in 2020.
His honors include the Xplorer Prize in 2020. The Zhang group focuses on condensed-matter quantum materials, quantum transport properties, and micro/nanodevice fabrication, with recent emphasis on quantum transport experiments in layered topological quantum materials and the fabrication of quantum functional devices. In 2019, Professor Zhang led his team in the experimental observation of the three-dimensional quantum Hall effect. This achievement attracted broad attention from both the media and specialists in the field, and was selected as one of China’s Top Ten Scientific Advances and one of the Top Ten News Items in Science and Technology in 2019. In 2022, the work received the First Prize of the Shenzhen Natural Science Award and the First Prize of the Guangdong Natural Science Award, and was included as a major physics achievement in the National 13th Five-Year Plan Exhibition on Scientific and Technological Innovation.
Abstract: The development of novel quantum materials and devices is closely intertwined with the emergence of energy and novel physical phenomena. At the same time, the intrinsic unknowns, diversity, and performance variability of these systems place increasing demands on transport studies. To address the high surface reactivity and poor process compatibility of many two-dimensional materials, we have developed an integrated device-fabrication workflow that combines high-yield mechanical exfoliation, low-damage dry transfer, atomically clean interfacial assembly, and in situ micro/nano-patterning.
This workflow substantially improves the reproducibility and reliability of devices based on unstable two-dimensional thin films, providing a robust foundation for precise control and intrinsic-property measurements. Then we present our recent exploratory work on transition-metal pentatellurides (ZrTe5/HfTe5) film devices, relative results including unconventional quantum Hall effect, nonlinear Hall effect and intrinsic physical properties.
Finally, from the perspectives of material screening, device fabrication and control, and the integration of multiple measurement techniques, we discuss feasible experimental routes and major challenges for realizing the three-dimensional quantum Hall effect (3D QHE) in broader classes of three-dimensional systems. We also present recent progress in new quantum materials. These material platforms are expected to provide important experimental grounds for exploring frontier problems such as Diophantine equations, topological knot structures, and irrational quantum statistics.