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arXiv · 2404.17409

Enhanced Whispering Gallery Mode Phase Shift using Indistinguishable Photon Pairs

Callum Jones·Antonio Vidiella-Barranco·Jolly Xavier·Frank Vollmer
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Abstract

We present a theoretical investigation of a whispering gallery mode (WGM) resonator coupled to a Mach-Zehnder interferometer (MZI) and show a bimodal coincidence transmission spectrum when the input state is an indistinguishable photon pair. This is due to the doubled WGM phase shift experienced by the path-entangled state in the interferometer. Further, we model the noise in a WGM resonance shift measurement comparing photon pairs with a coherent state. At least a four-fold improvement in the signal-to-noise ratio (SNR) is possible, with clear implications for quantum-enhanced WGM sensing.

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Callum Jones, Antonio Vidiella-Barranco, Jolly Xavier, Frank Vollmer. 2024-04-26. Enhanced Whispering Gallery Mode Phase Shift using Indistinguishable Photon Pairs. https://arxiv.org/abs/2404.17409

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