Polarization analysis and Density Functional Theory (DFT) simulations of the electric field in InN/GaN multiple quantum wells (MQWs)

TL;DR

This paper presents the first ab initio DFT simulations of InN/GaN multiquantum wells, confirming polarization charges at interfaces and analyzing the resulting electric fields that cause the Quantum Confined Stark Effect.

Contribution

It provides the first ab initio DFT analysis of InN/GaN MQWs, confirming polarization charges and electric fields using standard polarization parameters.

Findings

DFT confirms polarization charges at InN/GaN interfaces.

Electric fields cause electron-hole separation in QWs.

Results agree with polarization data and QCSE observations.

Abstract

Results of the first ab initio simulations of InN/GaN multiquantum well (MQW) system are presented. The DFT results confirm the presence of the polarization charge at InN/GaN interfaces, i.e. at polar InN/GaN heterostructures. These results show the potential jumps which is related to the presence of dipole layer at these interfaces. An electrostatic polarization analysis shows that the energy minimum condition can be used to obtain the field in InN/GaN system, employing standard polarization parameters. DFT results are in good agreement with polarization data confirming the existence of electric field leading to separation of electron and holes in QWs and emergence of Quantum Confined Stark Effect (QCSE).