Time-resolved resonance fluorescence (RF) is used to analyse electron tunneling between a single self-assembled quantum dot (QD) and an electron reservoir. In equilibrium, the RF intensity reflects the average electron occupation of the QD and exhibits a gate voltage dependence that is given by the Fermi distribution in the reservoir. In the time-resolved signal, however, we find that the relaxation rate for electron tunneling is independent of the occupation in the charge reservoir. Using a master equation approach which includes both the electron tunneling and the optical excitation/recombination, we are able to explain the experimental data by optical blocking, i. e. a reduced electron tunneling rate when the QD is occupied by an exciton.
@article{arxiv.1505.07682,
title = {Optical blocking of electron tunneling into a single self-assembled quantum dot},
author = {A. Kurzmann and B. Merkel and P. A. Labud and A. Ludwig and A. D. Wieck and A. Lorke and M. Geller},
journal= {arXiv preprint arXiv:1505.07682},
year = {2019}
}