Numerical Study of Energy Loss by a Nanomechanical Oscillator Coupled to a Cooper Pair Box

TL;DR

This study numerically investigates how coupling a nanomechanical oscillator to a Cooper pair box affects energy dissipation, revealing that the coupling can significantly enhance the oscillator's energy loss rate.

Contribution

It provides a detailed numerical analysis of energy loss dynamics in a coupled NMO-CPB system using stochastic Schrödinger equations with Lindblad operators.

Findings

Coupling accelerates energy loss in the NMO when CPB decay time is shorter.

Coupling results in slower energy decay of the CPB compared to uncoupled case.

Energy loss efficiency of the NMO is substantially increased through coupling.

Abstract

We calculate the dynamics of a nanomechanical oscillator (NMO) coupled capacitively to a Cooper pair box (CPB), by solving a stochastic Schrodinger equation with two Lindblad operators. 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 do the uncoupled NMO and CPB. The results show that the efficiency of energy loss by an NMO can be substantially increased if the NMO is coupled to a CPB.