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arXiv · 1505.07682

Optical blocking of electron tunneling into a single self-assembled quantum dot

A. Kurzmann·B. Merkel·P. A. Labud·A. Ludwig·A. D. Wieck·A. Lorke·M. Geller
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Abstract

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.

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A. Kurzmann, B. Merkel, P. A. Labud, A. Ludwig, A. D. Wieck, A. Lorke, M. Geller. 2015-05-28. Optical blocking of electron tunneling into a single self-assembled quantum dot. https://doi.org/10.1103/physrevlett.117.017401

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