Cyclotron-resonant exciton transfer between the nearly free and strongly localized radiative states of a two-dimensional hole gas in a high magnetic field

TL;DR

This paper reports the observation of cyclotron-resonant exciton transfer between free and localized states in a p-doped GaAs quantum well under high magnetic fields, revealing insights into exciton dynamics and localization.

Contribution

It demonstrates the magnetically tunable coupling between free and localized exciton states via cyclotron resonance in a two-dimensional hole gas.

Findings

Identification of avoided crossing in emission lines

Mapping of anti-crossing pattern for state identification

Observation of magnetically tunable coherent exciton state

Abstract

Avoided crossing of the emission lines of a nearly free positive trion and a cyclotron replica of an exciton bound to an interface acceptor has been observed in the magneto-photoluminescence spectra of p-doped GaAs quantum wells. Identification of the localized state depended on the precise mapping of the anti-crossing pattern. The underlying coupling is caused by an exciton transfer combined with a resonant cyclotron excitation of an additional hole. The emission spectrum of the resulting magnetically tunable coherent state probes weak localization in the quantum well.