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Annual Meeting Optical Society of America

Dynamic effects of focusing in an all-optical passive driven system

D. J. Jones, Donna Kay Bandy

Published Jan 1, 1990• 0 citations
Publisher

Abstract

By incorporating the radial dependence of the field, we explore the dynamical behavior of a passive optical system consisting of two focusing lenses, optically thin passive medium, and two partially transmitting mirrors, where one mirror functions as the entrance port for the external signal, and the second functions as the output coupler. The medium and the free-space diffraction are described by the Maxwell-Bloch equations and Kirchhoff's diffraction integral, respectively. A comparison between confocal resonators and nonconfocal resonators is made, and polarization effects are isolated.

DOI
10.1364/oam.1990.tup5

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We investigate the time-dependent behavior of an optically thin passive medium driven by an external coherent signal and show dynamical hysteresis effects in the regimes of large and small Fresnel numbers, positive and negative detuning, and changes in the cavity quality. We attribute shifting and deformation of the bistable loop and spatial hysteresis to free-space diffraction effects that are independent of diffusive and diffractive coupling within the medium. Since radial variation of the bistable loop is not present in the parameter space explored, we suggest that free-space diffraction does not contribute to this effect and adds weight to experimental findings that evidence diffusive coupling as the dominant mechanism for radial variations of the bistable loop.
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We investigate the phenomenon of self-diffraction in optically dense media for those cases where it is necessary to take into account the inverse effect of the medium on the field. Our study is based on a numerical analysis of the Maxwell–Bloch equations. This analysis reveals that, as the concentration of two-level systems increases, an anomalous response of four-wave mixing arises. This response is associated with the appearance of a self-diffraction signal in the negative-delay region and also with a faster decay of coherence in the system.