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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Augmenting the Sensing Performance of Entangled Photon Pairs through Asymmetry
Yoad Michael1, Isaac Jonas1, Leon Bello1
1BINA Center for Nanotechnology, Bar-Ilan University, Ramat Gan, 5290002, Israel.
Physical Review Letters
|November 5, 2021
Summary
Quantum interferometers using entangled pairs can distinguish signal loss from idler loss by observing SU(1,1) interference visibility. Coherent seeding enhances phase sensitivity, improving quantum imaging and interferometry performance.
Area of Science:
- Quantum optics
- Quantum information science
- Nonlinear quantum optics
Background:
- Quantum interferometers are crucial for precision measurements.
- Entangled photon pairs are key resources in quantum technologies.
- Asymmetric losses can degrade interferometer performance.
Purpose of the Study:
- To investigate the effects of asymmetric losses in a quantum nonlinear interferometer.
- To demonstrate how SU(1,1) interference visibility can distinguish between signal and idler loss.
- To explore methods for mitigating losses and enhancing phase sensitivity.
Main Methods:
- Theoretical analysis of quantum nonlinear interferometers.
- Experimental implementation using entangled photon pairs.
- Measurement of SU(1,1) interference visibility and phase sensitivity.
Main Results:
- Interference visibility directly correlates with the location of loss (signal vs. idler).
- Coherent seeding effectively mitigates losses in the idler mode.
- Sub-shot-noise phase detection is achievable even with significant idler mode losses.
Conclusions:
- Asymmetric losses in quantum interferometers can be diagnosed through interference visibility.
- Coherent seeding offers a practical method to improve loss tolerance in quantum sensing.
- These findings advance the development of quantum interferometry and imaging techniques.
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