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Entanglement generated by dissipation and steady state entanglement of two macroscopic objects
Hanna Krauter1, Christine A Muschik, Kasper Jensen
1Niels Bohr Institute, Danish Quantum Optics Center QUANTOP, Copenhagen University, Copenhagen, Denmark.
Physical Review Letters
|September 21, 2011
Summary
Researchers generated continuous entanglement between two macroscopic atomic ensembles using engineered dissipation. This robust quantum entanglement was maintained at room temperature for extended periods, challenging typical decoherence effects.
Area of Science:
- Quantum mechanics
- Quantum information science
- Atomic physics
Background:
- Entanglement is crucial for quantum information but typically inhibited by environmental interactions, especially in macroscopic systems.
- Dissipation usually leads to decoherence, destroying quantum entanglement.
- Previous research focused on protecting quantum systems from environmental noise.
Purpose of the Study:
- To demonstrate continuous generation of entanglement between macroscopic objects using engineered dissipation.
- To investigate the role of dissipation in creating and sustaining quantum entanglement.
- To achieve robust, steady-state entanglement at room temperature.
Main Methods:
- Utilized two atomic ensembles (approx. 10^12 atoms each) separated by 0.5 m.
- Engineered dissipation using precisely controlled laser and magnetic fields.
- Combined dissipative mechanisms with continuous measurement techniques.
- Coupled the atomic ensembles to vacuum modes of the electromagnetic field.
Main Results:
- Successfully generated entanglement between two macroscopic atomic ensembles.
- Achieved robust, event-ready entanglement maintained for 0.04 seconds at room temperature.
- Observed continuous generation of steady-state entanglement for up to 1 hour.
- Demonstrated that engineered dissipation can create, rather than destroy, entanglement.
Conclusions:
- Engineered dissipation can be a resource for generating quantum entanglement in macroscopic systems.
- This work provides a novel pathway for creating robust quantum entanglement under ambient conditions.
- The findings have significant implications for the development of quantum technologies and quantum information processing.
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