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One-way Einstein-Podolsky-Rosen steering via atomic coherence
Optics Express
|August 10, 2017
Summary
We demonstrate a new method for achieving one-way Einstein-Podolsky-Rosen (EPR) steering between field modes using atomic coherent effects. This technique offers robust quantum correlations, even across different frequencies like optical and microwave fields.
Area of Science:
- Quantum Optics
- Atomic Physics
- Quantum Information
Background:
- Einstein-Podolsky-Rosen (EPR) steering is a key quantum phenomenon demonstrating non-classical correlations.
- Achieving asymmetric or one-way EPR steering is crucial for quantum communication protocols.
- Atomic coherent effects offer a promising avenue for controlling quantum states and correlations.
Purpose of the Study:
- To explore asymmetric Einstein-Podolsky-Rosen (EPR) steering of field modes using atomic coherent effects.
- To investigate a resonant four-level atomic system in a double-cascade configuration for generating EPR steering.
- To analyze the feasibility of achieving steady-state one-way EPR steering between two cavity modes.
Main Methods:
- Utilizing a resonant four-level atomic system with a double-cascade configuration.
- Employing the dressed-atom Bogoliubov-field-mode approach for physical analysis.
- Investigating full-resonant interactions between classical fields, cavity modes, bare atoms, and Bogoliubov modes.
Main Results:
- Demonstrated that two cavity modes can achieve steady-state one-way EPR steering.
- Identified one-channel dissipation mediated by resonant coupling of dressed atoms as the mechanism.
- Showcased that one-way EPR steering can be induced by adjusting external field intensity.
- Confirmed EPR steering between field modes with large frequency differences (optical and microwave).
Conclusions:
- The proposed scheme enables robust one-way EPR steering, resistant to dynamic fluctuations and independent of the initial state.
- The ability to steer across disparate frequencies (optical and microwave) enhances practical quantum communication applications.
- Simple adjustment of external field intensity controls the observed one-way steering, offering experimental tractability.
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