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arXiv · 2406.13406

Photon number distribution of squeezed light from a silicon nitride microresonator measured without photon number resolving detectors

Emanuele Brusaschi·Massimo Borghi·Marcello Bacchi·Marco Liscidini·Matteo Galli·Daniele Bajoni
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Abstract

The measurement of the photon number distribution (PND) allows one to extract metrics of non-classicality of fundamental and technological relevance, but in principle it requires the use of detectors with photon number resolving (PNR) capabilities.In this work we reconstruct the PND of two-mode pulsed squeezed light generated from a silicon nitride microresonator using threshold detectors and variable optical attenuations. The PNDs are characterized up to 1.2 photons/pulse, through which we extracted an on-chip squeezing level of 6.2(2) dB and a noise reduction factor of -3.8(2) dB. The PNDs are successfully reconstructed up to an Hilbert space dimension of 6x6. The analysis performed on the photon-number basis allows us to characterize the influence of a spurious thermal background field that spoils the photon number correlations. We evaluate the impact of self and cross phase modulation on the generation efficiency in case of a pulsed pump, and validate the results through numerical simulations of the master equation of the system.

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Emanuele Brusaschi, Massimo Borghi, Marcello Bacchi, Marco Liscidini, Matteo Galli, Daniele Bajoni. 2024-06-19. Photon number distribution of squeezed light from a silicon nitride microresonator measured without photon number resolving detectors. https://doi.org/10.1364/opticaq.528566

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