Carrier-transfer dynamics between neutral and charged excitonic states in a single quantum dot probed with second-order photon correlation measurements

Abstract

We report a comprehensive investigation of carrier-transfer dynamics in a single InAs quantum dot (QD) based on second-order photon correlation measurements. The experimentally obtained auto and crosscorrelation functions as well as photoluminescence intensities are successfully explained on the basis of a series of rate equations with common excitation and also single-carrier-capture/escape rates to/from a QD. This approach enables us to understand the carrier-transfer dynamics responsible for the stability of a quantum two-level system formed in a single QD under various excitation conditions. We clarify that the transition between neutral and charged excitonic states is suppressed by one order of magnitude under quasiresonant excitation.