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Quantum Correlation in Squeezed Generalized Amplitude Damping Channels with Memory.
Youngmin Jeong1, Hyundong Shin2
1Department of Electronic Engineering, Kyung Hee University, Yongin-si, 17104, Korea.
Scientific Reports
|March 13, 2019
Summary
Quantum correlations like entanglement and discord can be preserved or generated in a squeezed generalized amplitude damping (SGAD) channel. The dynamics depend on initial states, channel parameters, and memory effects, with squeezing not affecting singlet-like states under correlated noise.
Area of Science:
- Quantum Information Science
- Quantum Communication
- Quantum Optics
Background:
- Quantum channels describe noise processes in quantum systems.
- Squeezed generalized amplitude damping (SGAD) channels model complex noise including bath squeezing, dissipation, and decoherence.
- Understanding quantum correlation dynamics under realistic noise is crucial for quantum technologies.
Purpose of the Study:
- To analyze the dynamics of quantum entanglement and discord in an SGAD channel with memory.
- To investigate how quantum correlations evolve in Werner-like mixed states transmitted through successive uses of the SGAD channel.
Main Methods:
- Derivation of a stochastic map to define the noisy quantum channel.
- Calculation of concurrence and discord for Werner-like mixed states.
- Analysis of the influence of initial states, channel parameters, and channel memory on quantum correlations.
Main Results:
- Quantum correlations (entanglement and discord) can be preserved or even generated within the SGAD channel.
- The evolution of quantum correlations is sensitive to the initial input states, channel parameters, and the degree of channel memory.
- The squeezing effect in the SGAD channel does not influence the dynamics of quantum correlation for singlet-like states when subjected to correlated noise.
Conclusions:
- The SGAD channel with memory offers potential for preserving and generating quantum correlations, contrary to simple noise models.
- Careful selection of initial states and channel parameters can optimize the preservation or generation of quantum correlations.
- Specific noise characteristics, like squeezing under correlated noise, may not always enhance quantum correlation dynamics for certain states.
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