Speaker
Prof.
Michele Campisi
(Scuola Normale Superiore)
Description
Since its inception about two centuries ago thermodynamics
has sparkled continuous interest and fundamental questions.
According to the second law no heat engine can have an
efficiency larger than Carnot’s efficiency. The latter can
be achieved by the Carnot engine, which however ideally
operates in infinite time, hence delivers null power. A
currently open question is whether the Carnot efficiency can
be achieved at finite power. Most of the previous works
addressed this question within the Onsager matrix formalism
of linear response theory. Here we pursue a different route
based on finite-size-scaling theory. We focus on quantum
Otto engines and show that when the working substance is at
the verge of a second order phase transition diverging
energy fluctuations can enable approaching the Carnot point
without sacrificing power. The rate of such approach is
dictated by the critical indices, thus showing the universal
character of our analysis.
Nature Communications, in press (2016) arXiv:1603.05024
Nature Communications, in press (2016) arXiv:1603.05024
Primary author
Prof.
Michele Campisi
(Scuola Normale Superiore)