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Nonlinear Dynamics in Optical Systems

Noise Power Spectrum Reduction Below Short-Noise Limit Due to the Radiation of a Laser with Intracavity Second-Harmonic Generation

A. I. Zhiliba

Published Jan 1, 1990• 0 citations
Publisher

Abstract

A source for generation of amplitude-squeezed states of the electromagnetic field in the process of the second harmonic generation (SHG) in the laser cavity is investigated. Amplitude squeezed states are resulted from the interaction of the laser mode whis a nonlinear cristal that is plased within the cavity of the laser.
DOI
10.1364/nldos.1990.stsa578

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The authors consider the problem of second harmonic generation in an optical cavity which contains both the laser and the nonlinear crystal. They calculate the spectrum of the amplitude fluctuations in the output field, for the mode which is generated by the laser. They focus on the case that the damping constant of this mode is much larger than all the other relaxation rates of the system, and show that in this limit the spectrum is correctly described by the universal normal form for two-photon processes. Finally, they show in general that in the framework of linearised theories the spectrum of the intensity fluctuations in the output field reduces exactly to the spectrum of squeezing of the amplitude quadrature component.
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