Polaronic Excitons in ZnCdSe/ZnSe Quantum Wells

TL;DR

This study investigates excitonic absorption in ZnCdSe/ZnSe quantum wells under magnetic fields, revealing the polaronic nature of excitons through experimental and theoretical analysis of exciton-phonon interactions.

Contribution

It provides the first detailed experimental and theoretical analysis confirming the polaronic character of excitons in ZnSe-based heterostructures.

Findings

Clear resolution of magneto-excitonic absorption resonant with heavy-hole excitons.

Experimental exciton binding energies match theoretical models including exciton-phonon interaction.

Strong evidence for the polaronic nature of excitons in the studied heterostructures.

Abstract

We present a detailed investigation of excitonic absorption in $Zn_{0.69}Cd_{0.31}Se/ZnSe$ quantum wells under the application of a perpendicular magnetic field. The large energy separation between heavy- and light-hole excitons allows us to clearly resolve and identify magneto-excitonic absorption resonant with the continuum edge of the 1S heavy-hole exciton. Experimental values of the exciton binding energy are compared with results of a theoretical model that includes the exciton-phonon interaction. The remarkable agreemeent found unambiguously indicates the predominant polaronic character of excitons in ZnSe-based heterostructures.