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arXiv · 2508.06255

Cavity-based optical switching via phase modulation in warm rubidium vapor

Georgia Booton·Tabijah Wasawo·William O. C. Davis·Cameron McGarry·Kristina R. Rusimova·Alex O. C. Davis·Josh Nunn·Peter J. Mosley
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Abstract

Optical switching remains a key outstanding challenge for scalable fault-tolerant photonic quantum computing due to the trade-off between speed, bandwidth, and loss. Scalable quantum photonics demands all three, to enable high computational clock rates and resource efficient scaling to large systems. We present a cavity-based optical switch that overcomes this limitation, demonstrating 22 ns rise time, insertion loss of 2.4 dB, and 17.5 dB extinction ratio. All-optical control is achieved via phase modulation of a signal field detuned from the near-degenerate two-photon absorption ladder in warm rubidium vapor. The ultimate performance of our switch, combining both speed and efficiency, will find applications in active multiplexing, loop-based quantum memory, and feedforward for quantum error-correction protocols.

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Georgia Booton, Tabijah Wasawo, William O. C. Davis, Cameron McGarry, Kristina R. Rusimova, Alex O. C. Davis, Josh Nunn, Peter J. Mosley. 2025-08-11. Cavity-based optical switching via phase modulation in warm rubidium vapor. https://doi.org/10.1103/r7xf-lptn

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