Abstract

A wide variety of nonlinear optical phenomena, such as stimulated Raman scattering[1], stimulated four-photon mixing[2], and sum-frequency generation[3], have been observed in optical fibers. For four-photon mixing in a fiber, phase matching condition has to be satisfied as well as conservation of energy. This has been successfully demonstrated both in multimode and single-mode fibers[4,5]. In a single-mode birefringent fiber, the birefringence in the fiber can compensate for the material dispersion[6,7]. Four-photon parametric process in single-mode birefringent fibers has been observed by Stolen et al. [6] when the pump polarization was along the slow axis and the Stokes and anti-Stokes pair were generated with a polarization along the fast axis with a large frequency shift. Later, Stenersen et al. [7] reported four-photon mixing with a relatively small frequency shift in highly birefringent single-mode fibers by divided pump between different polarization modes and phase-matched totally non-degenerate four-photon mixing by the pump, Stokes, and stimulated Raman Stokes to generate a new frequency. In this paper, we report the observation of various third-order nonlinear optical processes following parametric four-photon mixing in a highly birefringent fiber.

© 1989 Optical Society of America