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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.
Abstract:
In this paper, a novel InP/Bi2Se3 van der Waals heterojunction (vdWH) was constructed, and its geometric, electrical, interface, and optical properties were precisely calculated using first-principles calculations and finite-difference time-domain (FDTD). These results showed that this vdWH has excellent light absorption in the infrared range. The stability of the InP/Bi2Se3 vdWH was verified via binding energy calculations, elastic constant determination, phonon spectrum analysis, and ab initio molecular dynamics simulations (AIMD). The results demonstrated that the InP/Bi2Se3 vdWH has a type-II staggered band alignment with an indirect bandgap of 0.745 eV, and the bandgap can be tuned under the regulation of external strain and electric field. Moreover, the InP/Bi2Se3 vdWH possessed excellent carrier mobility, with electron mobilities of up to 4256.55 cm2 V-1 s-1 and 4194.46 cm2 V-1 s-1 in the x and y directions and hole mobilities of 2130.09 cm2 V-1 s-1 and 2258.32 cm2 V-1 s-1, and the absorption was also significantly enhanced, reaching 6.767 × 104 cm-1 under the irradiation of an incident light wave of 1.5 eV. Furthermore, the InP/Bi2Se3 vdWH photodetector was designed and modeled by FDTD. In addition, the calculation results indicated that the infrared light absorption of this vdWH-based photodetector reaches up to 60%, and the position of the maximum absorption peak is adjustable. The photocurrent density of this device in the near-infrared region was calculated to be 14.7 mA cm-2. In conclusion, this study confirmed that the InP/Bi2Se3 vdWH possesses remarkable competitiveness in the field of next-generation infrared detection.
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