Numerically "exact" simulations of a quantum Carnot cycle: Analysis using thermodynamic work diagrams

  title={Numerically "exact" simulations of a quantum Carnot cycle: Analysis using thermodynamic work diagrams},
  author={Shoki Koyanagi and Yoshitaka Tanimura},
  journal={The Journal of Chemical Physics},
We investigate the efficiency of a quantum Carnot engine based on open quantum dynamics theory. The model includes time-dependent external fields for the subsystems controlling the isothermal and isentropic processes and for the system--bath (SB) interactions controlling the transition between these processes. Numerical simulations are conducted in a nonperturbative and non-Markovian SB coupling regime using the hierarchical equations of motion under these fields at different cycle frequencies… 

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