arXiv:0907.2720 · Physical Review A

Cavity-QED models of switches for attojoule-scale nanophotonic logic

Hideo Mabuchi

Published Oct 22, 2009• 41 citations

Abstract

Quantum optical input-output models are described for a class of optical switches based on cavity quantum electrodynamics (QED) with a single multilevel atom (or comparable bound system of charges) coupled simultaneously to several resonant field modes. A recent limit theorem for quantum stochastic differential equations is used to show that such models converge to a simple scattering matrix in a type of strong-coupling limit that seems natural for nanophotonic systems. Numerical integration is used to show that the behavior of the prelimit model approximates that of the simple scattering matrix in a realistic regime for the physical parameters and that it is possible in the proposed cavity-QED configuration for low-power optical signals to switch higher-power signals at attojoule energy scales.

DOI: 10.1103/physreva.80.045802

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