Stochastic pumping of heat: approaching the Carnot efficiency.
نویسنده
چکیده
Random noise can generate a unidirectional heat current across asymmetric nano-objects in the absence (or against) a temperature gradient. We present a minimal model for a molecular-level stochastic heat pump that may operate arbitrarily close to the Carnot efficiency. The model consists a fluctuating molecular unit coupled to two solids characterized by distinct phonon spectral properties. Heat pumping persists for a broad range of system and bath parameters. Furthermore, by filtering the reservoirs' phonons the pump efficiency can approach the Carnot limit.
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عنوان ژورنال:
- Physical review letters
دوره 101 26 شماره
صفحات -
تاریخ انتشار 2008