RGC Senior Research Fellow Scheme

Biography

Chair Professor and Dr William M W Mong Professor of Nanoscience in Department of Physics at The Hong Kong University of Science and Technology
Research focus on the theoretical studies of possible topological states in correlated or non-equilibrium realistic material systems
SRFS project — to examine three subjects related to strongly correlated and non-equilibrium topological states. 1) Addressing Landau Parameters in Topological Semi-Metals, Dr Dai aim to analyze chiral zero sound acoustic waves in these semi-metals using first-principle calculations. For materials with moderate correlation, Dr Dai'll employ a linear response theory rooted in density functional theory. For strongly correlated materials, the Gutzwiller variational method will compute susceptibility, leading to the Landau parameters. 2) Turning to 2D Moire Super-Lattice Systems, especially twisted bilayer graphene (TBG) and transition metal dichalcogenides (TMD), Dr Dai has modeled TBG's electronic properties, emphasizing its correlated and topological aspects. Leveraging pseudo zeroth Landau levels, the model will elucidate TBG's phase diagram, accounting for temperature, filling, and interaction strength. 3) Dr Dai'll probe Topological Many-Body Floquet States, focusing on 2D Moire superlattice systems like twisted multi-layer graphene or TMD under a robust periodic electric field.
Awards and Honours:
- RGC Senior Research Fellow (2023)
- James C. McGroddy Prize for New Materials (2019)
- Fellow of American Physical Society (2019)

Project Title

Searching for New Topological Matter in Correlated and Non-equilibrium Systems

Award Citation

The RGC proudly bestows the Senior Fellowship upon Professor Xi Dai in recognition of his pioneering and transformative contributions to the realm of condensed matter physics and topological materials. Professor Dai’s ground-breaking work on the Bi2Se3 material family, as elucidated in his seminal paper [Nature Physics 5, 438, (2009)], has paved the way for the identification and understanding of Z2 topological insulators, an area of research that has garnered global acclaim and is now foundational in the study of quantum materials.

A visionary in his field, Professor Dai foresaw the potential of magnetically doped Bi2Se3 or Bi2Te3 thin films to exhibit the quantum anomalous Hall effect (QAHE), a prediction that was later affirmed experimentally in 2013 [Science 329, 61, (2010)].

Further strengthening his indelible mark in the field, Professor Dai's predictions encompassed a series of topological semimetals, including the first experimentally confirmed Na3Bi Dirac semimetal, TaAs Weyl semimetal family, and type II Weyl semimetal WTe2, each adding significant momentum to ongoing research endeavors in quantum materials.

In celebrating his monumental achievements, the RGC is honored to confer upon Professor Xi Dai this Senior Fellowship, acknowledging his enduring impact on the field and inspiring future generations of physicists.