Abstract
Artificial heterojunctions, which can host a rich variety of quantum states and phases, are primary workhorses in the emerging second quantum revolution. It is critical to discover and understand functional phases of quantum matter through heterostructure design and translate them into technological advances. In this talk, I will focus on the development and investigation of high-quality heterojunctions and superlattices, and the exploration of the unique quantum transport properties of these novel material platforms, particularly unconventional superconductivity. First, I will show how superconductivity can be induced in high-mobility GaAs through the proximity effect by constructing a transparent interface. Then, I will present a unique approach to achieving possible chiral superconductivity by introducing chiral molecules into two-dimensional superconductors TaS2, through van der Waals integration. By conducting phase-sensitive measurements, a half-flux quantum phase shift is observed. Additionally, a magnetic field-free superconducting diode effect is found, suggesting spontaneous time-reversal symmetry breaking. Inspired by these findings, I will also discuss the exciting opportunities of van der Waals integration for creating new artificial heterojunctions with designable chemical compositions, dimensionality, interlayer distances, and structural motifs, which open up brand new platforms for both fundamental studies and quantum technologies.
Biosketch
Dr. Zhong Wan is currently a postdoctoral research scholar at UCLA in the Department of Chemistry and Biochemistry, working with Prof. Xiangfeng Duan. Before joining UCLA, he earned his Ph.D. in condensed matter physics from Purdue University in 2018 under the guidance of Prof. Leonid Rokhinson. His research interests encompass quantum materials engineering, the development of nanoscale devices, and the exploration of emergent low-temperature quantum transport properties. Dr. Wan has received the 2020 Postdoctoral Research Award from the Department of Chemistry and Biochemistry and nominations for the 2021, 2023 Chancellor’s Award for Postdoctoral Research at UCLA, respectively.
Please contact phweb@ust.hk should you have questions about the talk.
