English

Quantum thermodynamic processes: A control theory for machine cycles

Statistical Mechanics 2009-11-13 v2

Abstract

The minimal set of thermodynamic control parameters consists of a statistical (thermal) and a mechanical one. These suffice to introduce all the pertinent thermodynamic variables; thermodynamic processes can then be defined as paths on this 2-dimensional control plane. Putting aside coherence we show that for a large class of quantum objects with discrete spectra and for the cycles considered the Carnot efficiency applies as a universal upper bound. In the dynamic (finite time) regime renormalized thermodynamic variables allow to include non-equilibrium phenomena in a systematic way. The machine function ceases to exist in the large speed limit; the way, in which this limit is reached, depends on the type of cycle considered.

Keywords

Cite

@article{arxiv.0712.0534,
  title  = {Quantum thermodynamic processes: A control theory for machine cycles},
  author = {Jan Birjukov and Thomas Jahnke and Günter Mahler},
  journal= {arXiv preprint arXiv:0712.0534},
  year   = {2009}
}

Comments

14 pages, 12 figures, Replaced by version accepted for publication in European Physical Journal B

R2 v1 2026-06-21T09:50:18.868Z