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arXiv · 1701.01304

Demonstrating the decoupling regime of the electron-phonon interaction in a quantum dot using chirped optical excitation

Timo Kaldewey·Sebastian Lüker·Andreas V. Kuhlmann·Sascha R. Valentin·Jean-Michel Chauveau·Arne Ludwig·Andreas D. Wieck·Doris E. Reiter·Tilmann Kuhn·Richard J. Warburton
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Abstract

Excitation of a semiconductor quantum dot with a chirped laser pulse allows excitons to be created by rapid adiabatic passage. In quantum dots this process can be greatly hindered by the coupling to phonons. Here we add a high chirp rate to ultra-short laser pulses and use these pulses to excite a single quantum dot. We demonstrate that we enter a regime where the exciton-phonon coupling is effective for small pulse areas, while for higher pulse areas a decoupling of the exciton from the phonons occurs. We thus discover a reappearance of rapid adiabatic passage, in analogy to the predicted reappearance of Rabi rotations at high pulse areas. The measured results are in good agreement with theoretical calculations.

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Timo Kaldewey, Sebastian Lüker, Andreas V. Kuhlmann, Sascha R. Valentin, Jean-Michel Chauveau, Arne Ludwig, Andreas D. Wieck, Doris E. Reiter, Tilmann Kuhn, Richard J. Warburton. 2017-01-05. Demonstrating the decoupling regime of the electron-phonon interaction in a quantum dot using chirped optical excitation. https://doi.org/10.1103/physrevb.95.241306

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