Bounds on fluctuations for ensembles of quantum thermal machines

  title={Bounds on fluctuations for ensembles of quantum thermal machines},
  author={Matthew Gerry and Na’im Kalantar and Dvira Segal},
  journal={Journal of Physics A: Mathematical and Theoretical},
We study universal aspects of fluctuations in an ensemble of noninteracting continuous quantum thermal machines in the steady state limit. Considering an individual machine, such as a refrigerator, in which relative fluctuations (and high order cumulants) of the cooling heat current to the absorbed heat current, $\eta^{(n)}$, are upper-bounded, $\eta^{(n)}\leq \eta_C^n$ with $n\geq 2$ and $\eta_C$ the Carnot efficiency, we prove that an {\it ensemble} of $N$ distinct machines similarly… 

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