arXiv:cond-mat/0301252 · Physical Review B

Quantum measurement of a coupled nanomechanical resonator–Cooper-pair box system

E. K. Twyeffort Irish, Keith Schwab

Published Oct 15, 2003• 195 citations

Abstract

We show two effects as a result of considering the second-order correction to the spectrum of a nanomechanical resonator electrostatically coupled to a Cooper-pair box. The spectrum of the Cooper-pair box is modified in a way which depends on the Fock state of the resonator. Similarly, the frequency of the resonator becomes dependent upon the state of the Cooper-pair box. We consider whether these frequency shifts could be utilized to prepare the nanomechanical resonator in a Fock state, to perform a quantum non-demolition measurement of the resonator Fock state, and to distinguish the phase states of the Cooper-pair box.

DOI: 10.1103/physrevb.68.155311

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