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arXiv · 2111.13653

Optical transparency induced by a largely Purcell-enhanced quantum dot in a polarization-degenerate cavity

Harjot Singh·Demitry Farfurnik·Zhouchen Luo·Allan S. Bracker·Samuel G. Carter·Edo Waks
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Abstract

Optically-active spin systems coupled to photonic cavities with high cooperativity can generate strong light-matter interactions, a key ingredient in quantum networks. But obtaining high cooperativities for quantum information processing often involves the use of photonic crystal cavities that feature a poor optical access from the free space, especially to circularly polarized light required for the coherent control of the spin. Here, we demonstrate coupling with cooperativity as high as $8$ of an InAs/GaAs quantum dot to a fabricated bullseye cavity that provides nearly degenerate and Gaussian polarization modes for efficient optical accessing. We observe spontaneous emission lifetimes of the quantum dot as short as $80$ ps (a $\approx 15$ Purcell enhancement) and a $\approx 80\%$ transparency of light reflected from the cavity. Leveraging the induced transparency for photon switching while coherently controlling the quantum dot spin could contribute to ongoing efforts of establishing quantum networks.

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Harjot Singh, Demitry Farfurnik, Zhouchen Luo, Allan S. Bracker, Samuel G. Carter, Edo Waks. 2021-11-26. Optical transparency induced by a largely Purcell-enhanced quantum dot in a polarization-degenerate cavity. https://doi.org/10.1021/acs.nanolett.2c03098

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