Related Experiment Video
Updated: May 16, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Polarization-driven topological insulator transition in a GaN/InN/GaN quantum well
M S Miao1, Q Yan, C G Van de Walle
1Materials Research Laboratory and Materials Department, University of California, Santa Barbara, California 93106-5050, USA. miaoms@engineering.ucsb.edu
Abstract:
Topological insulator (TI) states have been demonstrated in materials with a narrow gap and large spin-orbit interactions (SOI). Here we demonstrate that nanoscale engineering can also give rise to a TI state, even in conventional semiconductors with a sizable gap and small SOI. Based on advanced first-principles calculations combined with an effective low-energy k · p Hamiltonian, we show that the intrinsic polarization of materials can be utilized to simultaneously reduce the energy gap and enhance the SOI, driving the system to a TI state. The proposed system consists of ultrathin InN layers embedded into GaN, a layer structure that is experimentally achievable.
Related Concept Videos
Semiconductors
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Dielectric Polarization in a Capacitor
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...
Potential Due to a Polarized Object
Induced Electric Dipoles
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Types of Semiconductors

