  The dissipative properties of an optical cavity can be effectively controlled
by placing it in a feedback loop where the light at the cavity output is
detected and the corresponding signal is used to modulate the amplitude of a
laser field which drives the cavity itself. Here we show that this effect can
be exploited to improve the performance of an optomechanical heat engine which
makes use of polariton excitations as working fluid. In particular we
demonstrate that, by employing a positive feedback close to the instability
threshold, it is possible to operate this engine also under parameters regimes
which are not usable without feedback, and which may significantly ease the
practical implementation of this device.

Quantum Physics