2008/04/14 by A. D. Armour, M. P. Blencowe · 2 citations
Computer Science · Physics and Astronomy · #Force Microscopy Techniques and Applications #Mechanical and Optical Resonators #Quantum Information and Cryptography #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1088/1367-2630/10/9/095004
published as New J. Phys. 10, 095004 (2008) · Submitted to New Journal of Physics: Special Issue "Mechanical Systems at the Quantum Limit"
arxiv created 2008/04/14 · openalex publication_date 2008/09/30 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose a scheme in which the quantum coherence of a nanomechanical resonator can be probed using a superconducting qubit. We consider a mechanical resonator coupled capacitively to a Cooper-pair box and assume that the superconducting qubit is tuned to the degeneracy point so that its coherence time is maximised and the electro-mechanical coupling can be approximated by a dispersive Hamiltonian. When the qubit is prepared in a superposition of states this drives the mechanical resonator progressively into a superposition which in turn leads to apparent decoherence of the qubit. Applying a suitable control pulse to the qubit allows its population to be inverted resulting in a reversal of the resonator dynamics. However, the resonator's interactions with its environment mean that the dynamics is not completely reversible. We show that this irreversibility is largely due to the decoherence of the mechanical resonator and can be inferred from appropriate measurements on the qubit alone. Using estimates for the parameters involved based on a specific realization of the system we show that it should be possible to carry out this scheme with existing device technology.