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Dissipative dynamics in a quantum bistable system: crossover from weak to strong damping
Luca Magazzù1,2, Davide Valenti1, Bernardo Spagnolo1,2,3
1Dipartimento di Fisica e Chimica, Università di Palermo, Viale delle Scienze, Edificio 18, I-90128 Palermo, Italy.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 15, 2015
Summary
We studied quantum bistable systems interacting with heat baths beyond standard approximations. Our findings reveal distinct dynamical regimes based on temperature and coupling strength.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Statistical mechanics
Background:
- Investigating quantum systems coupled to environments is crucial for understanding phenomena like decoherence.
- The spin-boson model is a standard but limited framework for such studies.
Purpose of the Study:
- To explore the dissipative dynamics of a quantum bistable system beyond the spin-boson approximation.
- To develop a more accurate theoretical framework for quantum dissipation.
Main Methods:
- Utilized the path-integral approach to quantum dissipation.
- Developed a novel approximation scheme based on timescale separation.
- Derived a generalized master equation for population dynamics.
Main Results:
- Successfully investigated dynamics across a wide range of temperatures and coupling strengths.
- Identified different dynamical regimes in the quantum bistable system.
- Presented a phase diagram illustrating these regimes.
Conclusions:
- The proposed approximation offers a more comprehensive understanding of quantum dissipation.
- The findings are relevant for systems exhibiting tunneling and environmental coupling.
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