2024-2026 Kavli Heising-Simons Junior Fellow
Faculty Advisor: Professor Feng Wang
Ziyu Xiang is currently a 4th-year Applied Science & Technology PhD candidate in the Prof. Feng Wang’s group. His research work mainly focuses on experimental condensed matter physics, particularly the behavior of strongly correlated electrons in two-dimensional (2D) heterostructures, by applying scanning tunneling microscope (STM). Before attending UC Berkeley, Ziyu obtained his B.S. degree in physics from University of Chinese Academy of Sciences. He enjoys skiing and calligraphy.
Ziyu’s recent research aim is to create new imaging methods and utilize them to explore two distinct insulating quantum state systems: the 2D Wigner crystals and α-RuCl3. The Wigner crystals, a phenomenon predicted by Eugene Wigner in 1934, remains mystery in its real-space structure. In this project, Ziyu aims to directly visualize the 2D Wigner crystals and unravel its quantum melting behavior. Ziyu will create a high charge spatial resolution STM/STS method, by directing measuring the in-gap tunneling current between the tip and sample. To take a non-invasive measurement, the electric field between the tip and sample can be balanced so the tip perturbation could be minimized. For another interesting system, α-RuCl3, an insulating magnetic material, serves as a candidate for the Kitaev quantum spin liquid (QSL). Despite its insulating nature at high charge density, Ziyu plans to pioneer a novel STM/STS method to probe the charge density distribution of α-RuCl3 by equipment with a monolayer transition metal dichalcogenide (TMD) on the top of α-RuCl3 as a sensing layer. By tunneling current into the TMD layer, the STM/STS can be performed to visualize the charge density distribution in TMD, which can reflect the charge distribution in the α-RuCl3. Through visualizing the charge density distribution in the α-RuCl3, this project potentially contributes to the spatial imaging of the Kitaev QSL and revealing signatures of Majorana fermions.