  Under a general framework, shortcuts to adiabatic processes are shown to be
possible in classical systems. We then study the distribution function of the
work done on a small system initially prepared at thermal equilibrium. It is
found that the work fluctuations can be significantly reduced via shortcuts to
adiabatic processes. For example, in the classical case probabilities of having
very large or almost zero work values are suppressed. In the quantum case
negative work may be totally removed from the otherwise non-positive-definite
work values. We also apply our findings to a micro Otto-cycle-based heat
engine. It is shown that the use of shortcuts, which directly enhances the
engine output power, can also increase the heat engine efficiency
substantially, in both quantum and classical regimes.
