Relative Abundance of Topological Order in Exfoliable Two-Dimensional Insulators

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Computing

Background:

• Quantum spin Hall insulators are 2D materials with unique electronic properties like helical edge states.
• These materials offer potential for low-dissipation transport, spin filtering, and topological quantum computing.
• Discovering room-temperature quantum spin Hall insulators is crucial for technological advancement.

Purpose of the Study:

• To screen a large database of 2D materials for novel quantum spin Hall insulators.
• To identify materials exhibiting non-trivial topological order at room temperature.
• To provide candidates for experimental validation and technological applications.

Main Methods:

• Screening of 1825 experimentally known 2D material monolayers.
• Utilizing density-functional theory (DFT) and many-body perturbation theory simulations.
• Assessing mechanical stability and topological order under strain.

Main Results:

• Identification of 13 candidate quantum spin Hall insulators.
• Discovery of AsCuLi2 and Pt2HgSe3 (platinum jacutingaite) as high-performing candidates.
• Identification of Pd2HgSe3 (palladium jacutingaite) as a novel Kane-Mele quantum spin Hall insulator.
• Confirmation of mechanical stability and topological order in several promising materials.

Conclusions:

• A significant number of 2D materials exhibit topological order, with approximately 1% of those screened showing promise.
• The identified materials offer viable pathways for experimental research in spintronics and topological quantum computing.
• This work provides a curated list of candidate materials for future development of quantum spin Hall devices.