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Published on: November 11, 2013
Oscillatory dynamics and non-Markovian memory in dissipative quantum systems.
D M Kennes1, O Kashuba, M Pletyukhov
1Institut für Theorie der Statistischen Physik, RWTH Aachen University and JARA-Fundamentals of Future Information Technology, 52056 Aachen, Germany.
Physical Review Letters
|March 26, 2013
Summary
Quantum systems show unique oscillatory dynamics near transitions, differing from classical models. Non-Markovian memory effects are crucial for understanding quantum system evolution after a quantum quench.
Area of Science:
- Quantum mechanics
- Statistical physics
- Condensed matter theory
Background:
- Understanding the dynamics of small quantum systems interacting with their environment is fundamental.
- Dissipative environments introduce complexity, leading to phenomena like decoherence and energy loss.
- The transition from coherent to incoherent dynamics is a key area of study in open quantum systems.
Purpose of the Study:
- To investigate the nonequilibrium dynamics of a small quantum system coupled to a dissipative environment.
- To compare the oscillatory dynamics of quantum systems near a coherent-incoherent transition with classical damped harmonic oscillators.
- To elucidate the role of non-Markovian memory effects in quantum dynamics after a quantum quench.
Main Methods:
- Theoretical modeling of a small quantum system.
- Coupling the quantum system to a dissipative environment.
- Analyzing the time evolution of the system after a quantum quench.
- Employing analytical and numerical techniques to study dynamics.
Main Results:
- The oscillatory dynamics near the coherent-to-incoherent transition in quantum systems differ significantly from classical damped harmonic oscillators.
- Non-Markovian memory effects are shown to play a prominent role in the system's time evolution post-quantum quench.
- The study highlights unique quantum features not present in classical analogues.
Conclusions:
- The behavior of quantum systems in dissipative environments exhibits distinct characteristics compared to classical systems.
- Non-Markovianity is a critical factor that must be considered for accurate predictions of quantum dynamics.
- These findings have implications for quantum information processing and the understanding of quantum thermodynamics.
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