Related Experiment Video
Updated: Mar 17, 2026

Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices
Published on: July 11, 2025
Band inversion and topological aspects in a TiNI monolayer
Aizhu Wang1, Zhenhai Wang2, Aijun Du3
1School of Physics and State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China. zmw@sdu.edu.cn and School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, QLD 4001, Australia. aijun.du@qut.edu.au.
Abstract:
To achieve a device application of the quantum spin Hall (QSH) effect, increasing the critical temperature is crucial. A two-dimensional topological insulator (2D-TI) with a sizeable bulk band gap is one of the most promising strategies to reach this goal. Using first-principles calculations, we propose a new 2D-TI, titanium nitride iodide (TiNI) monolayer, which can be exfoliated from a bulk TiNI crystal, thanks to the weak interlayer interaction. We demonstrate that the TiNI monolayer has an inverted band structure accompanied by topologically nontrivial states characterized by a topological invariant of Z2 = 1. The band gap (∼50 meV) opened due to spin-orbit coupling (SOC) is available for achieving the QSH effect at room temperature. The band inversion and topologically nontrivial states are robust under external strain, suggesting that the 2D TiNI monolayer lattice could be a versatile platform for hosting nontrivial topological states with potential applications in 2D spintronics and computer technology.
More Related Videos
13:56Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
09:00Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Related Concept Videos
Band Theory
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
Valence Bond Theory
The Pauli Exclusion Principle
Energy Bands in Solids
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...