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Published on: November 11, 2013
Nonlocal memory effects in the dynamics of open quantum systems
Elsi-Mari Laine1, Heinz-Peter Breuer, Jyrki Piilo
1Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turun yliopisto, Finland.
Physical Review Letters
|September 26, 2012
Summary
Initial correlations in composite environments can create nonlocal dynamics in open quantum systems, even with local interactions. This research reveals how environmental correlations can induce memory effects, shifting dynamics from Markovian to non-Markovian.
Area of Science:
- Quantum Mechanics
- Quantum Information Science
Background:
- Open quantum systems are typically described by Markovian dynamics, assuming weak system-environment interactions.
- Local system-environment interactions are conventionally thought to preserve Markovianity.
Purpose of the Study:
- To investigate the generation of nonlocal dynamical maps in open quantum systems via local interactions.
- To explore the role of environmental correlations in influencing open quantum system dynamics.
Main Methods:
- Utilized a generic decoherence process driven by a local interaction Hamiltonian.
- Modeled a system of two entangled photons interacting with two dephasing environments.
Main Results:
- Demonstrated that initial correlations in a composite environment can induce nonlocal open system dynamics with memory effects.
- Showed that local dynamics can remain Markovian while the overall system exhibits non-Markovian behavior.
- Established a direct link between the degree of memory effects and the initial environmental state's correlation.
Conclusions:
- Initial environmental correlations can lead to non-Markovian dynamics in open quantum systems, challenging conventional understanding.
- Enlarging an open quantum system by incorporating correlated environments can transition its dynamics from Markovian to non-Markovian.
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