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Steady State Entanglement in Cavity QED
Optics Express
|June 12, 2009
Summary
We studied steady-state entanglement in an open quantum system. Optimal atom-field coupling maximizes entanglement, with cross-correlation functions indicating its presence.
Area of Science:
- Quantum Optics
- Open Quantum Systems
Background:
- Investigating steady-state entanglement is crucial for quantum information processing.
- Open quantum systems, like atoms in driven cavities, are fundamental for studying quantum phenomena.
Purpose of the Study:
- To explore steady-state entanglement in a single atom within a driven optical cavity.
- To identify optimal conditions for maximizing entanglement and methods for its measurement.
Main Methods:
- Modeling an open quantum system with cavity loss and spontaneous emission.
- Analyzing system behavior under weak driving fields.
- Calculating normalized cross-correlation functions.
Main Results:
- The system achieves a steady pure state under weak driving.
- An optimal atom-field coupling strength maximizes entanglement.
- Cavity-enhanced spontaneous emission influences entanglement at higher coupling.
- Normalized cross-correlation functions, specifically intensity-field correlations, indicate entanglement.
Conclusions:
- Steady-state entanglement in driven optical cavities is achievable and controllable.
- Optimizing atom-field coupling is key to maximizing entanglement.
- Cross-correlation functions provide a viable method for measuring quantum entanglement in such systems.
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