Quantum Otto Cycle with Inner Friction

Antonio Alecce, Fernando Galve, Nicola Lo Gullo, Francesco Plastina, Roberta Zambrini, Luca Dell’Anna

Published Jan 1, 2015• 0 citations

Abstract

In this poster we addressed a finite time working quantum Otto cycle. The working substance of this cycle is characterized by non interacting disordered qubits. If we think at qubits as spins in a magnetic field, "disorder" refers to a random misalignment between the single spins and the direction of the external field. Such field drives, in a finite time, the adiabatic branches. On the other hand the isochoric transformations are assumed to be two thermalizations at different temperature T_c and T_h. Power, net work, efficiency and efficiency at maximum power are obtained, according to different choices of T_c/T_h and of the misalignment probability distribution across the substance. Such probability distributions are assumed to be Gaussian with mean values, for the misalignment, equal to zero.

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