arXiv:1812.06879 · Journal of Mathematical Physics

Time evolution of coupled multimode and multiresonator optomechanical systems

David Edward Bruschi

Published Jun 1, 2019• 18 citations

Abstract

We study the time evolution of bosonic systems where multiple driven bosonic modes of light interact with multiple mechanical resonators through arbitrary, time-dependent, optomechanicallike interactions. We find the analytical expression for the full time evolution of the system and compute the expectation value of relevant quantities of interest. Among the most interesting ones, we are able to compute the first-order quantum bipartite coherence between pairs of subsystems, and the analytical expression for the mixedness induced by the nonlinear interaction in the reduced state of the mechanical oscillators. Finally, we also compare our results with a linearized version of the system, and we find a regime where there are qualitative and quantitative differences in the behavior of some measurable quantities. Our results can, therefore, be used to describe the full time-evolution of the system to characterize its nonlinear character and explore the validity of the linearization approach.

DOI: 10.1063/1.5106409

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