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Journal of Modern Optics

Sub-Poissonian photon squeezing and entanglement in optical chain second harmonic generation

Rafael Julius, Abdel-Baset M.A. Ibrahim, Hichem Eleuch, P. K. Choudhury

Published Apr 18, 2019• 21 citations
Publisher

Abstract

Nonclassical properties exhibited by a chain of cavity modes second harmonic generation in coupled oscillators system, designed by using multichannel optical waveguides, is explored. The solution for the Hamiltonian of the coupled-modes driven by coherent excitation is obtained via an exact formulation of the normal-ordered Fokker-Planck equation. Nonclassical effects, namely the sub-Poissonian photons, squeezing and entanglement are noticed. Multichannel coupling of the coupled oscillators induces new possibilities for correlation between the modes in different channels, henceforth, provides an effective way towards manipulation of quantum light.

DOI
10.1080/09500340.2019.1603408

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The squeezing and sub-Poissonian eects of light in third harmonic generation are investigated based on the fully quantum mechanical approach up to the rst order Hamiltonian interaction in gt, where g is the coupling constant between the modes per second and t is the interaction time between the waves during the process in a nonlinear medium.The coupled Heisenberg equations of motion involving real and imaginary parts of the quadrature operators are established.The occurrence of amplitude squeezing eects in both the quadratures of the radiation eld in the fundamental mode is investigated and found to be dependent on the selective phase values of the eld amplitude.The photon statistics of the pump mode in this process have also been investigated and found to be sub-Poissonian in nature.It is shown that for particular phase values the amplitude squeezing and sub-Poissonian photon statistics of light occur simultaneously.It is observed that there is no possibility to produce squeezed light in the harmonic mode up to rst-order interaction in gt.Further, it is found that the normal squeezing in the harmonic mode directly depends upon the amplitude-cubed squeezing of the initial pump eld to the case of second-order interaction in gt.This gives a method of converting higher-order (amplitude-cubed) squeezing of the fundamental mode into normal squeezing of the harmonic mode and vice versa.
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