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arXiv · 2404.10708

Keeping the photon in the dark: Enabling full quantum dot control by chirped pulses and magnetic fields

Florian Kappe·René Schwarz·Yusuf Karli·Thomas Bracht·Vollrath M. Axt·Armando Rastelli·Vikas Remesh·Doris E. Reiter·Gregor Weihs
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Abstract

Because dark excitons in quantum dots are not directly optically accessible, so far they have not played a significant role in using quantum dots for photon generation. They possess significantly longer lifetimes than their brighter counterparts and hence offer enormous potential for photon storage or manipulation. In this work, we demonstrate an all-optical storage and retrieval of the spin-forbidden dark exciton in a quantum dot from the ground state employing chirped pulses and an in-plane magnetic field. Our experimental findings are in excellent agreement with theoretical predictions of the dynamics calculated using state-of-the-art product tensor methods. Our scheme enables an all-optical control of dark states without relying on any preceding decays. This opens up a new dimension for optimal quantum control and time-bin entangled photon pair generation from quantum dots.

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Florian Kappe, René Schwarz, Yusuf Karli, Thomas Bracht, Vollrath M. Axt, Armando Rastelli, Vikas Remesh, Doris E. Reiter, Gregor Weihs. 2024-04-16. Keeping the photon in the dark: Enabling full quantum dot control by chirped pulses and magnetic fields. https://arxiv.org/abs/2404.10708

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