Signatures of chaotic and non-chaotic-like behaviour in a non-linear quantum oscillator through photon detection

摘要

The driven non-linear duffing osillator is a very good, and standard, exampleof a quantum mechanical system from which classical-like orbits can berecovered from unravellings of the master equation. In order to generated suchtrajectories in the phase space of this oscillator in this paper we use a thequantum jumps unravelling together with a suitable application of thecorrespondence principle. We analyse the measured readout by considering thepower spectra of photon counts produced by the quantum jumps. Here we show thatlocalisation of the wave packet from the measurement of the oscillator by thephoton detector produces a concomitant structure in the power spectra of themeasured output. Furthermore, we demonstrate that this spectral analysis can beused to distinguish between different modes of the underlying dynamics of theoscillator.