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Updated: Apr 25, 2026

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
Type-II band alignment and enhanced optical properties in InP/Bi2Se3 van der Waals heterojunctions: a
Xinhao Xu1, Xin Guo1,2, Youchun Ma1,3
1State Key Laboratory of Extreme Environment Optoelectronic Dynamic Measurement Technology and Instrument, North University of China, Taiyuan, 030051, People's Republic of China. guoxin2019@nuc.edu.cn.
A novel InP/Bi2Se3 van der Waals heterojunction (vdWH) exhibits excellent infrared light absorption and carrier mobility. This stable vdWH shows tunable bandgap properties, making it promising for next-generation infrared detectors.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Van der Waals heterojunctions (vdWHs) are crucial for advanced electronic and optoelectronic devices.
- Indium phosphide (InP) and Bismuth selenide (Bi2Se3) are promising materials for optoelectronic applications.
Purpose of the Study:
- To construct and investigate the properties of a novel InP/Bi2Se3 van der Waals heterojunction (vdWH).
- To evaluate its potential for infrared detection applications.
Main Methods:
- First-principles calculations were employed to determine geometric, electronic, interface, and optical properties.
- Finite-difference time-domain (FDTD) simulations were used for optical property analysis and device modeling.
- Stability was verified through binding energy, elastic constants, phonon spectra, and ab initio molecular dynamics (AIMD) simulations.
Main Results:
- The InP/Bi2Se3 vdWH exhibits a type-II staggered band alignment with an indirect bandgap of 0.745 eV, tunable via strain and electric fields.
- Excellent carrier mobility (electron: ~4200 cm2V-1s-1, hole: ~2200 cm2V-1s-1) and enhanced infrared light absorption (up to 6.767 × 10^4 cm^-1 at 1.5 eV) were observed.
- A vdWH-based photodetector demonstrated up to 60% infrared light absorption with an adjustable peak and a photocurrent density of 14.7 mA cm^-2.
Conclusions:
- The InP/Bi2Se3 vdWH is a stable and promising material for next-generation infrared detection.
- Its tunable optoelectronic properties and high performance indicate significant potential for advanced photodetector applications.
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