Excitation Induced Dephasing in Semiconductor Quantum Dots

TL;DR

This paper develops a quantum kinetic theory to explain excitation induced dephasing in semiconductor quantum dots, highlighting the importance of frequency-dependent broadening and nonlinear shifts, and showing differences from quantum wells and bulk materials.

Contribution

It introduces a microscopic model for excitation induced dephasing in quantum dots, emphasizing the roles of frequency dependence and nonlinear resonance shifts.

Findings

Dephasing involves frequency-dependent broadening.

Nonlinear resonance shifts are essential for explanation.

Dephasing behavior differs from quantum wells and bulk excitons.

Abstract

A quantum kinetic theory is used to compute excitation induced dephasing in semiconductor quantum dots due to the Coulomb interaction with a continuum of states, such as a quantum well or a wetting layer. It is shown that a frequency dependent broadening together with nonlinear resonance shifts are needed for a microscopic explanation of the excitation induced dephasing in such a system, and that excitation induced dephasing for a quantum-dot excitonic resonance is different from quantum-well and bulk excitons.