Optical evidence of polaron interaction in InAs/GaAs quantum dots

Photoluminescence (PL) and resonant PL (RPL) have been performed at low temperatures in a number of InAs/GaAs quantum dots (QD’s) whose emission energies range from 1.4 to 1.08 eV. A simple, standard electron-phonon interaction model reproduces PL and RPL spectra well. The value of the electron-phonon interaction $S$ is large for small QD’s and evolves to small values for large, well-formed QD’s. This trend is consistent with recent experimental results in InAs QD’s and provides an experimental basis to recent theoretical speculations.