Related Experiment Video
Updated: Jul 14, 2025

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Effect of external electric field on the electronic properties of the AlAs/SiC van der Waals heterostructure
Zicheng Zhang1, Changxin Wan1, Heng Li2,3
1College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing 210023, China. menglan@njupt.edu.cn.
Abstract:
Type-II van der Waals (vdW) heterostructures are regarded as the optimum candidates for unipolar electronic device applications due to their capacity for spontaneous electron-hole separation. Here, we studied the electronic properties of the AlAs/SiC vdW heterostructure via density functional theory calculations. Results show that the conduction band minimum (CBM) and valence band maximum (VBM) of this heterostructure are mainly contributed by different materials, illustrating that the AlAs/SiC heterostructure has a type-II band alignment. Interestingly, this heterostructure possesses flat valence bands near the Fermi level. In addition, under the modulation of external electric field ranging between -1 V Å-1∼0.8 V Å-1, the band gap of the heterostructure can be tuned continuously, while the band structure maintains a stable type-II band alignment with flat top valence bands. When the electric field exceeds -1 or 0.8 V Å-1, the heterostructure transitions from semiconductor material to metal, indicating the tunability of electronic properties under external fields. These results indicate that the AlAs/SiC heterostructure shows great potential for application in high-performance optoelectronic devices and a strong correlation may exist in this system.
Related Concept Videos
π Electron Effects on Chemical Shift: Overview
Metal-Semiconductor Junctions
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Biasing of Metal-Semiconductor Junctions
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
Fermi Level Dynamics
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...
Types of Semiconductors

