Efficiency fluctuations in microscopic machines

Nanoscale machines are strongly influenced by thermal
fluctuations, contrary to their macroscopic counterparts.
As a consequence, we need to talk about efficiency
distributions  and not just an average efficiency. Can such
a distribution have any universal properties? In earlier
work, it was shown, for a particular class of
non-equilibrium systems, that, in the large time limit, this
distribution always has a “universal” shape. In recent work,
we have shown that if we extend this class of systems, the
efficiency distribution can be one of  several types. We are
able to classify when and how these different types occur as
well as the exact form of the efficiency distribution in
each case.