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Extracting work from random collisions: A model of a quantum heat engine
Vahid Shaghaghi1,2, G Massimo Palma3,4, Giuliano Benenti1,2,4
1Center for Nonlinear and Complex Systems, Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio 11, 22100 Como, Italy.
Physical Review. E
|April 16, 2022
Summary
This study explores the efficiency of a single-qubit Otto engine fueled by random collisions. Fluctuations arise from the nonequilibrium hot reservoir, impacting ergotropy and efficiency distributions.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Open quantum systems
Background:
- Investigates quantum heat engines and batteries.
- Utilizes a collision model for open system dynamics.
- Focuses on single-qubit systems interacting with reservoirs.
Purpose of the Study:
- Analyze the statistical distribution of ergotropy and efficiency.
- Examine a single-qubit Otto engine fueled by random collisions.
- Contrast a nonequilibrium hot reservoir with a thermal one.
Main Methods:
- Employs a collision model to describe qubit-reservoir interactions.
- Models the working fluid as a single qubit.
- Considers a nonequilibrium hot reservoir and a zero-temperature cold reservoir.
Main Results:
- Identifies fluctuations in ergotropy, heat, and work due to random collisions.
- Observes that fluctuations decrease with the size of the hot reservoir qudits.
- Finds that the mean efficiency matches the macroscopic efficiency for a thermal reservoir.
Conclusions:
- The distribution of efficiencies for the nonequilibrium Otto engine does not support finite moments.
- The mean of efficiencies does not coincide with the macroscopic efficiency.
- Highlights the impact of reservoirNonequilibrium on quantum engine performance.
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