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Updated: Nov 12, 2025
Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Highly tunable electronic structure and linear dichroism in 90° twisted α-phosphorus carbide bilayer: a
Weiwei Liu1, Hongwei Bao, Yan Li
1State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China. liyan0802@xjtu.edu.cn mafei@mail.xjtu.edu.cn.
Abstract:
α-Phosphorus carbide (α-PC) shares a similar puckered structure with black phosphorus and has a high carrier mobility, showing great application potential in the future nano-electronic devices. Based on first-principles calculations, we reveal that an interlayer twist angle of 90° results in a symmetric band dispersion and spatial separation of electronic states in the α-PC bilayer, leading to isotropic electrical transport. Nevertheless, the anisotropic electronic states can be rebooted by introducing an out-of-plane electrostatic potential or an in-plane deformation potential, both of which can break the energy degeneracy and continuously modulate the bandgap of the 90° twisted bilayer. This highly tunable band structure can also induce a directionally exchangeable optical linear dichroism by flipping the voltage sign or changing the strain mode. These results indicate that the combination of the interlayer twist and gating/strain technique provides great flexibility to control the anisotropic behaviors in 2D puckered materials.
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