arXiv:0805.4401 · Physical Review B

Numerical study of energy loss by a nanomechanical oscillator coupled to a Cooper-pair box

Rakesh P. Tiwari, D. Stroud

Published Jun 20, 2008• 7 citations

Abstract

We calculate the dynamics of a nanomechanical oscillator (NMO) coupled capacitively to a Cooper-pair box (CPB) by solving a stochastic Schr\"odinger equation with two Lindblad operators [Commun. Math. Phys. 48, 119 (1976).]. Both the NMO and the CPB are assumed dissipative, and the coupling is treated within the rotating wave approximation. We show numerically that, if the CPB decay time is smaller than the NMO decay time, the coupled NMO will lose energy faster and the coupled CPB more slowly than the uncoupled NMO and CPB do. The results show that the efficiency of energy loss by an NMO can be substantially increased if the NMO is coupled to a CPB.

DOI: 10.1103/physrevb.77.214520

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