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Quantum 2.0 Conference and Exhibition

Coherent States in Ring Resonators Outperform Any Quantum Probe Single-pass Absorption Estimation Strategy

Alexandre Belsley, Euan J. Allen, Animesh Datta, Jonathan C. F. Matthews

Published Jan 1, 2022• 0 citations
Publisher

Abstract

By leveraging interference and resonance enhancement effects, we find all-pass ring resonators with coherent-state probes can estimate absorption more precisely than any quantum probe single-pass strategy, including those using squeezed or Fock states.
DOI
10.1364/quantum.2022.qtu4c.2

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Quantum states of light have been shown to enhance precision in absorption estimation over classical strategies. By exploiting interference and resonant enhancement effects, we show that coherent-state probes in all-pass ring resonators can outperform any quantum probe single-pass strategy even when normalized by the mean input photon number. We also find that under optimal conditions coherent-state probes equal the performance of arbitrarily bright pure single-mode squeezed probes in all-pass ring resonators.
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