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Time-resolved characterization of pulsed squeezed light from a strongly driven silicon nitride microresonator

Emanuele Brusaschi1,*, Marco Liscidini1, Matteo Galli1, Daniele Bajoni2, and Massimo Borghi1

  • *Contact author: emanuele.brusaschi01@universitadipavia.it
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Phys. Rev. Applied 25, 034008 – Published 3 March, 2026

DOI: https://doi.org/10.1103/37rx-fzfp

Abstract

Silicon nitride microresonators driven by strong pump pulses can generate squeezed light in a dominant spectral-temporal mode, a central resource for continuous-variable quantum computation. In the high parametric gain regime, several effects, including self- and cross-phase modulation as well as time-ordering corrections, become significant and can degrade source performance. In this work, we comprehensively investigate the generation of squeezed light from a silicon nitride resonator under pulsed pumping, spanning from low to high parametric gain up to approximately 16 photons/pulse. We experimentally study how the average photon number and the first- and second-order correlations of the squeezed marginal modes evolve with increasing pulse energy, across various frequency detunings and pulse durations. Furthermore, we analyze the errors introduced by multipair emissions in estimating the joint temporal intensity via time-resolved coincidence measurements. We propose and demonstrate an error-correction strategy based on the marginal distributions of time-resolved multiphoton events. Our results provide a practical strategy for optimizing the gain and the temporal mode structure of pulsed squeezed light sources in microresonators, elucidating the physical mechanisms and limitations that govern source performance in the high-gain regime.

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Corrections

5 October, 2026

Correction: Figures 3(a) and 3(b) mistakenly displayed the same graph and have been replaced.

Article Text

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Outline

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Phys. Rev. Applied 25, 034008– Published 3 March, 2026
  • Received 7 October 2025
  • Revised 22 December 2025
  • Accepted 9 January 2026
  • Corrected 5 October 2026
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