  The performance of endoreversible thermal machines operating at finite power
constitutes one of the main challenges of nonequilibrium classical and quantum
thermodynamics, engineering and others. Here we address the role of a so far
unexplored (but very realistic) ingredient: asymmetric interaction times
between system and reservoirs. We consider one of the simplest thermal ma
chines, composed of a quantum dot interacting sequentially with two different
reservoirs of heat and particles. Distinct optimization protocols are analyzed
in the framework of stochastic thermodynamics. Results reveal that asymmetric
time switchings plays a fundamental role in enhancing the power output and that
maximizations can provide efficiencies at maximum power greater than the
endoreversible Curzon-Ahlborn efficiency for a broad range of revervoir
temperatures.
