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arXiv · 2401.01447

Circular photonic crystal grating design for charge-tunable quantum light sources in the telecom C-band

Chenxi Ma·Jingzhong Yang·Pengji Li·Eddy P. Rugeramigabo·Michael Zopf·Fei Ding
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Abstract

Efficient generation of entangled photon pairs at telecom wavelengths is a key ingredient for long-range quantum networks. While embedding semiconductor quantum dots into hybrid circular Bragg gratings has proven effective, it conflicts with $p$-$i$-$n$ diode heterostructures which offer superior coherence. We propose and analyze hybrid circular photonic crystal gratings, incorporating air holes to facilitate charge carrier transport without compromising optical properties. Through numerical simulations, a broad cavity mode with a Purcell factor of 23 enhancing both exciton and biexciton transitions, and exceptional collection efficiency of 92.4% into an objective with numerical aperture of 0.7 are achieved. Furthermore, our design demonstrates direct coupling efficiency over 90% into a single-mode fiber over the entire telecom C-band. The hybrid circular photonic crystal grating thereby emerges as a promising solution for the efficient generation of highly coherent, polarization-entangled photon pairs.

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Chenxi Ma, Jingzhong Yang, Pengji Li, Eddy P. Rugeramigabo, Michael Zopf, Fei Ding. 2024-01-02. Circular photonic crystal grating design for charge-tunable quantum light sources in the telecom C-band. https://doi.org/10.1364/oe.517758

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