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Robust Asymptotic Entanglement under Multipartite Collective Dephasing
Edoardo G Carnio1,2, Andreas Buchleitner1,3, Manuel Gessner1
1Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Straße 3, 79104 Freiburg, Germany.
Physical Review Letters
|July 17, 2015
Summary
We found a way to preserve quantum entanglement in multiple atoms interacting with a fluctuating field. This analytic solution applies to various field conditions and maintains entanglement during decoherence.
Area of Science:
- Quantum physics
- Atomic physics
- Quantum information science
Background:
- Collective dephasing dynamics describe how quantum states lose coherence.
- Fluctuating external fields can disrupt quantum systems.
- Entanglement is a key resource for quantum technologies.
Purpose of the Study:
- To derive an analytic solution for the dephasing dynamics of N noninteracting atoms.
- To identify states whose entanglement is preserved under fluctuating fields.
- To analyze the impact of arbitrary field orientations and spectral distributions.
Main Methods:
- Derivation of an analytic solution for ensemble-averaged collective dephasing.
- Utilizing a Kraus map to characterize state evolution.
- Analysis of entanglement preservation under incoherent evolution.
Main Results:
- An analytic solution for collective dephasing dynamics was obtained.
- Families of states preserving entanglement were identified.
- Preservation of entanglement was shown to be independent of field orientation and spectral distribution.
Conclusions:
- The derived analytic solution provides a method for protecting quantum entanglement.
- This work is relevant for developing robust quantum information processing systems.
- The findings are applicable to systems with arbitrary field fluctuation spectral distributions.
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