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Updated: May 7, 2026
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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
Towards arbitrary time-frequency mode squeezing with self-conjugated mode squeezing in fiber.
Han Liu1, Meng Lon Iu2, Noor Hamdash2
1The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON, Canada. qwerty.liu@mail.utoronto.ca.
Nature Communications
|July 15, 2025
Summary
Researchers relaxed the modal constraint for squeezed light generation using optical parametric amplification. This allows for squeezing in arbitrary time-frequency modes, achieving record levels in fiber sources.
Area of Science:
- Quantum optics
- Nonlinear optics
Background:
- Optical parametric amplification (OPA) generates squeezed light.
- Squeezing detection traditionally requires adherence to device-specific time-frequency eigenmodes.
- This modal constraint limits the flexibility of squeezed light utilization.
Purpose of the Study:
- To investigate the relaxation of modal constraints in squeezed light generation via OPA.
- To demonstrate that squeezing can be detected in arbitrary time-frequency modes.
- To achieve high levels of squeezing in fiber-based sources.
Main Methods:
- Theoretical analysis under continuous-wave pump and broadband phase-matching approximation.
- Identification of self-conjugated spectral symmetry as a condition for approximating squeezing eigenmodes.
- Experimental demonstration using a high-efficiency, low-loss all-fiber OPA source.
- Partial homodyne detection for heralding squeezing in arbitrary modes.
Main Results:
- Demonstrated relaxation of the modal constraint for squeezed light generation.
- Achieved 4.38 ± 0.11 dB squeezing on partially coherent self-conjugated modes.
- Achieved 0.88 ± 0.09 dB squeezing on chaotic self-conjugated modes.
- Obtained 7.50 ± 0.12 dB squeezing using a bichromatic self-conjugated mode, a record for guided-wave sources.
Conclusions:
- The modal constraint for squeezed light generation can be significantly relaxed.
- Self-conjugated time-frequency modes enable squeezing detection in arbitrary modes.
- This work paves the way for more versatile applications of squeezed light from fiber sources.
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