Colloquium: Yiping Wang, Columbia University
Hidden State and Dynamics in Moiré Quantum Matter
Event Details:
- Date: February 24, 2026
- Time: 3:45 - 4:45 PM
- Location: 1080 Physics Research Building
- Faculty Host: Mike Chini
Abstract
Exploring and understanding quantum phases that emerge from interactions between electrons and nuclei is a central theme of condensed matter physics. In recent years, moiré interfaces of two-dimensional van der Waals crystals have emerged as a versatile platform for studying such phases, offering extreme tunability of electronic correlations and topology. At the same time, many of these phases leave only subtle signatures in equilibrium, making them difficult to identify using conventional static probes.
In this talk, I will show how non-equilibrium measurements provide a new route to detect hidden ground states in moiré quantum materials. I will focus on twisted MoTe₂ bilayers, which host a remarkably rich phase diagram and the landmark realization of the fractional quantum anomalous Hall effect. I will present the discovery of a zoo of correlated and topological states at fractional fillings that evade detection by transport and static optical measurements. In addition, by directly accessing the relevant electronic and phononic timescales, I will reveal the microscopic origins of different phases. Together, these results not only expose hidden states but also highlight the dynamic nature of topological protection, motivating further experimental and theoretical exploration of exotic quantum phases.
Bio
Yiping Wang is a Max Planck New York Center Postdoctoral Fellow at Columbia University, working with Professors Xiaoyang Zhu and James Hone. Her research focuses on light–matter interactions in quantum materials, with an emphasis on correlated and topological phenomena. Prior to joining Columbia, she earned her Ph.D. in physics from Boston College in 2022 under the supervision of Professor Kenneth Burch. During her doctoral work, she advanced collective-mode excitations as probes of emergent quantum phases.