Coherent Excitonic Coupling in an Asymmetric Double InGaAs Quantum Well Arises from Many-Body Effects

TL;DR

This paper investigates the coherent excitonic coupling in an asymmetric double InGaAs quantum well, revealing that many-body interactions are responsible for the observed coupling through advanced optical spectroscopy and theoretical modeling.

Contribution

It demonstrates that many-body effects are the origin of coherent interwell excitonic coupling in asymmetric quantum wells, supported by experimental and theoretical analysis.

Findings

Coherent and incoherent contributions to excitonic coupling are distinguished.

Many-body interactions are identified as the source of interwell coupling.

Optical two-dimensional spectroscopy effectively characterizes excitonic interactions.

Abstract

We study an asymmetric double InGaAs quantum well using optical two-dimensional coherent spectroscopy. The collection of zero-quantum, one-quantum, and two-quantum two-dimensional spectra provides a unique and comprehensive picture of the double well coherent optical response. Coherent and incoherent contributions to the coupling between the two quantum well excitons are clearly separated. An excellent agreement with density matrix calculations reveals that coherent interwell coupling originates from many-body interactions.