Decoherence in current induced forces: Application to adiabatic quantum motors

LUCAS FERNÁNDEZ-ALCÁZAR; RAÚL A. BUSTOS-MARÚN; HORACIO M. PASTAWSKI

PHYSICAL REVIEW B - SOLID STATE

Institute of Physics

Lugar: Nueva yor; Año: 2015 vol. 92 p. 75406 - 75406

0556-2805

Current induced forces are not only related with the discrete nature of electrons but also with its quantumcharacter. It is natural then to wonder about the effect of decoherence. Here, we develop the theory of currentinduced forces including dephasing processes and we apply it to study adiabatic quantum motors (AQMs). Thetheory is based on B¨uttiker?s fictitious probe model, which here is reformulated for this particular case.We provethat it accomplishes the fluctuation-dissipation theorem. We also show that, in spite of decoherence, the totalwork performed by the current induced forces remains equal to the pumped charge per cycle times the voltage.We find that decoherence affects not only the current induced forces of the system but also its intrinsic frictionand noise, modifying in a nontrivial way the efficiency of AQMs.We apply the theory to study an AQM inspiredby a classical peristaltic pump where we surprisingly find that decoherence can play a crucial role by triggeringits operation. Our results can help to understand how environmentally induced dephasing affects the quantumbehavior of nanomechanical devices.