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arXiv · 0902.3612

Indistinguishable photons from the resonance fluorescence of a single quantum dot in a microcavity

Serkan Ates·Sven Markus Ulrich·Stephan Reitzenstein·Andreas Loeffler·Alfred Forchel·Peter Michler
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Abstract

We demonstrate purely resonant continuous-wave optical laser excitation to coherently prepare an excitonic state of a single semiconductor quantum dot (QDs) inside a high quality pillar microcavity. As a direct proof of QD resonance fluorescence, the evolution from a single emission line to the characteristic Mollow triplet10 is observed under increasing pump power. By controlled utilization of weak coupling between the emitter and the fundamental cavity mode through Purcell-enhancement of the radiative decay, a strong suppression of pure dephasing is achieved, which reflects in close to Fourier transform-limited and highly indistinguishable photons with a visibility contrast of 90%. Our experiments reveal the model-like character of the coupled QD-microcavity system as a promising source for the generation of ideal photons at the quantum limit. From a technological perspective, the vertical cavity symmetry -- with optional dynamic tunability -- provides strongly directed light emission which appears very desirable for future integrated emitter devices.

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Serkan Ates, Sven Markus Ulrich, Stephan Reitzenstein, Andreas Loeffler, Alfred Forchel, Peter Michler. 2009-02-20. Indistinguishable photons from the resonance fluorescence of a single quantum dot in a microcavity. https://doi.org/10.1103/physrevlett.103.167402

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