Effect of anharmonicity of the strain energy on band offsets in semiconductor nanostructures

Olga L. Lazarenkova, Jet Propulsion Laboratory, California Institute of Technology
Paul von Allmen, Jet Propulsion Laboratory, California Institute of Technology
Fabiano Oyafuso, Jet Propulsion Laboratory, California Institute of Technology
Seungwon Lee, Jet Propulsion Laboratory, California Institute of Technology
Gerhard Klimeck, Jet Propulsion Laboratory, California Institute of Technology; Network for Computational Nanotechnology, Electrical and Computer Engineering, Purdue University

Abstract

Anharmonicity of the interatomic potential is taken into account for the quantitative simulation of the conduction and valence band offsets for strained semiconductor heterostructures. The anharmonicity leads to a weaker compressive hydrostatic strain than that obtained with the commonly used quasiharmonic approximation of the Keating model. Compared to experiment, inclusion of the anharmonicity in the simulation of strained InAs/GaAs nanostructures results in an improvement of the electron band offset computed on an atomistic level by up to 100 meV.