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Updated: Jun 8, 2026
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Field-quadrature and photon-number correlations produced by parametric processes
C J McKinstrie1, M Karlsson, Z Tong
1Bell Laboratories, Alcatel–Lucent, Holmdel, New Jersey 07733, USA. mckinstrie@alcatel-lucent.com
Optics Express
|October 14, 2010
Summary
This study derives formulas for quadrature and number correlations in multi-mode parametric processes. Phase-sensitive links offer significantly lower noise figures and improved signal-idler correlation compared to phase-insensitive systems.
Area of Science:
- Quantum optics
- Nonlinear optics
- Quantum information science
Background:
- Previous work derived formulas for field-quadrature and photon-number variances in multi-mode parametric processes.
- This paper extends the analysis to include quadrature and number correlations.
Purpose of the Study:
- To derive formulas for quadrature and number correlations in multi-mode parametric processes.
- To analyze the properties of basic devices (amplifiers, attenuators, frequency converters) and composite systems (cascaded amplifiers, communication links).
- To investigate the performance of phase-sensitive (PS) versus phase-insensitive (PI) systems, particularly in communication links.
Main Methods:
- Derivation of analytical formulas for quadrature and number correlations.
- Analysis of parametric devices (amplifiers, attenuators) and their effects on signal-to-noise ratios (SNRs).
- Evaluation of composite systems, including cascaded amplifiers and two-mode PS communication links.
Main Results:
- Parametric amplifiers generate correlated idlers or correlate existing mode pairs; attenuators decorrelate modes.
- Amplifiers can decrease (PI) or increase (PS) mode SNRs, while attenuators always decrease SNRs.
- Two-mode PS links demonstrate 6-dB lower noise figures than PI links and produce highly correlated signal-idler pairs, enabling electronic noise cancellation.
Conclusions:
- Quadrature and number correlations are crucial for understanding multi-mode parametric processes.
- Phase-sensitive devices and links offer significant advantages in noise reduction and correlation, particularly for quantum communication.
- The derived formulas provide a framework for designing and analyzing advanced quantum optical systems.
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