Temperature dependent high resolution resonant spectroscopy on a charged quantum dot

We present temperature dependent high resolution resonant optical spectroscopy on a single, negatively charged InGaAs quantum dot. We performed laser transmission measurements yielding the natural linewidth of the excitonic ground state transition of a quantum dot in a temperature range from 4.2 K up to 25 K. Here, we describe the linewidth evolution and the temperature induced red shift of the resonance energy with simple models based on the exciton–phonon coupling in the quantum dot. The resonant spectroscopy measurements are complemented with results from non‐resonant PL measurements on the very same quantum dot. Here we observe a simple linear behavior of the linewidth according to an effect of a fluctuating environment. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)