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Conference on Lasers and Electro-Optics

Covariance Matrix Reconstruction of Nonclassical Light Generated On-Chip

Roger Alfredo Kögler, Gabriel C. Rickli, Renato R. Domeneguetti, Xingchen Ji, Alexander L. Gaeta, Michal F. Lipson, M. Martinelli, P. Nussenzveig

Published Jan 1, 2022• 0 citations
Publisher

Abstract

We reconstruct covariance matrices of two-mode states generated in an above-threshold on-chip optical parametric oscillator. Up to 2.3 dB squeezing is directly observed and all quadratures are measured, as a function of pump intensity.
DOI
10.1364/cleo_at.2022.jw3b.130

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We measured the covariance matrix of the fields generated in an integrated third-order optical parametric oscillator operating above threshold. We observed up to (2.3 ± 0.3) dB of squeezing in amplitude difference and inferred (4.9 ± 0.7) dB of on-chip squeezing, while an excess of noise for the sum of conjugated quadratures hinders the entanglement. The degradation of amplitude correlations and state purity for increasing the pump power is consistent with the observed growth of the phase noise of the fields, showing the necessity of strategies for phase noise control aiming at entanglement generation in these systems.
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