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arXiv:1710.08519 · Physical Review A

Squeezed-state evolution and entanglement in lossy coupled-resonator optical waveguides

Hossein Seifoory, Marc M. Dignam

Published Feb 26, 2018• 9 citations
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Abstract

We investigate theoretically the temporal evolution of a squeezed state in lossy coupled-cavity systems. We present a general formalism based upon the tight-binding approximation and apply this to a two-cavity system as well as to a coupled-resonator optical waveguide in a photonic crystal. We derive analytical expressions for the number of photons and the quadrature noise in each cavity as a function of time when the initial excited state is a squeezed state in one of the cavities. We also analytically evaluate the time-dependent cross correlation between the photons in different cavities to evaluate the degree of quantum entanglement. We demonstrate that loss in such coupled-cavity systems cannot be treated using simple exponential factors. Finally, we also derive approximate analytic expressions for the maximum photon number, maximum squeezing, and maximum entanglement for cavities far from the initially excited cavity in a lossless coupled-resonator optical waveguide.

DOI
10.1103/physreva.97.023840

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We investigate theoretically the properties of squeezed states generated using degenerate parametric down conversion in lossy cavities. We show that the Lindblad master equation, which governs the evolution of this system, has as its solution a squeezed thermal state with an effective temperature and squeezing parameter that depends on time. We derive analytical solutions for the time-evolution of quadrature noise, thermal photon number, squeezing parameter, and total photon number under different pumping regimes. We also find the steady state limits of the quadrature noises and discuss the $ g^{(2)} $ factor of the generated light inside the cavity in the steady state.
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