Realizing quantum spin Hall insulators and correlated topology in ternary transition metal chalcogenides
Abstract
The convergence of topology and correlation is a rapidly growing field in condensed matter. Of particular importance is to realize topological order, which leads to intriguing phenomena like fractionalization, long-range entanglement, and non-Abelian anyons. The exploration of topological order is fundamentally interesting, and their robust macroscopic quantum effects offer great potential for realizing topologically protected quantum computing. This research focuses on the quantum spin Hall (QSH) insulator, which features an insulating bulk and helical edge conduction protected by time-reversal symmetry. The interplay between the QSH topology and electron correlations remains unexplored but holds the promise for time-reversal-symmetric topological order, such as the fractional QSH and the helical quantum spin liquid. Unfortunately, the scarcity of suitable materials has impeded investigations into these states. A highly promising material platform is the monolayer of van der Waals (vdW) ternary transition metal chalcogenides MM Te4 (M=Ta, Nb; M =Ir, Rh). By leveraging their novel electronic properties, we aim to realize high-temperature QSH and strong electron correlations and search for time-reversal-symmetric fractional QSH state. More technically, monolayer MM Te4 possess single-particle QSH topology, quasi-1D electronic structures, and high density of states arising from tunable low-energy van Hove singularities. These exceptional characteristics make them highly desirable for investigating the interplay between topology and correlation. To detect the QSH and correlation in these materials, we will employ a range of approaches, including vdW sample fabrication, quantum electron transport analysis, and optical sensing of electronic compressibility. The significance of this research lies in its potential of realizing time-reversal-symmetric topological order and advancing topological quantum computing. Ultimately, this will enhance the capabilities of the Air Force and DoD in quantum information processing, secure communication, and high-end computing.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2025
- Source ID
- FA95502410117
Entities
People
- Qiong Ma
Organizations
- Air Force Office of Scientific Research
- Boston College
- United States Air Force