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Updated: Jun 13, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum entanglement in coupled lossy waveguides.
Amit Rai1, Sumanta Das, G S Agarwal
1Department of Physics, Oklahoma State University,Stillwater, Oklahoma 74078, USA. amit.rai@okstate.edu
Optics Express
|April 15, 2010
Summary
Coupled waveguides show promise for quantum circuits, maintaining entanglement even with losses. This research explores their robustness for quantum architectures and coherent phenomena.
Area of Science:
- Quantum optics
- Quantum information science
- Solid-state physics
Background:
- Coupled waveguides are fundamental components in integrated photonic devices.
- Entanglement is a key resource for quantum information processing.
- Understanding loss effects is crucial for practical quantum technologies.
Purpose of the Study:
- To investigate the suitability of coupled waveguides for quantum circuits.
- To analyze entanglement properties in waveguide systems under different conditions.
- To assess the impact of signal loss on entanglement dynamics.
Main Methods:
- Analytical calculations of entanglement measures (logarithmic negativity).
- Modeling light generation via down-conversion (low and high gain regimes).
- Simulating entanglement dynamics in waveguide modes considering loss.
- Utilizing realistic waveguide structures in the analysis.
Main Results:
- Explicit analytical results for entanglement (logarithmic negativity) were derived for various input states.
- The study quantified the effect of loss on the entanglement dynamics of waveguide modes.
- Waveguide structures demonstrated reasonable robustness against signal loss.
Conclusions:
- Coupled waveguides are viable building blocks for quantum circuits and architectures.
- These structures are suitable for studying coherent phenomena, such as quantum random walks.
- The robustness against loss suggests practical applicability in current quantum technology development.
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