Journal of Physics Conference Series

Quantum measurement and the quantum to classical transition in a non-linear quantum oscillator

M. J. Everitt, William J. Munro, Timothy P. Spiller

Published Jul 8, 2011• 2 citations

Abstract

We study a non-linear quantum mechanical oscillator, acting as a measurement device. Candidate systems for realising such apparatus range from superconducting devices through to nano-mechanical resonators. The measurement device comprises an oscillator circuit where the dynamics of expectation values, in its correspondence limit, are either chaotic-like or periodic depending on the measured state of the quantum object – in this case a qubit. In a previous work we showed how the classical like trajectories of such a quantum system can act as a model of a projective measurement process. Here we investigate the quantum to classical transition of the measurement device and postulate criteria for realisation of an effective implementation of such a device.

DOI: 10.1088/1742-6596/306/1/012045

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