Abstract: An optical fiber switch in accordance with the present invention includes an optical fiber, a gate signal generating system, and a coupling system. The optical fiber has a birefringence between 10.sup.-5 and 10.sup.-6 and an effective area of at least 40 square microns. The generating system generates a gating signal having a power level which induces non-linear birefringence in the optical fiber causing an input signal in the optical fiber to switch polarization modes. The coupling system couples the input signal and the gating signal into the optical fiber. The optical fiber in the optical switch is designed to minimize non-linear effects which would degrade an input signal in the optical fiber switch. In particular, the optical fiber switch is designed to reduce the amount of power required by the gating signal to switch the input signal in the optical fiber, thus reducing the possibility of the fiber fuse and the generation of higher order solitons through Raman effects.

Abstract: A fiber optic system in accordance with the present invention includes an optical fiber, a coupling device, and a system for generating a pump signal. The optical fiber has a birefringence which preserves polarization and has a first polarization mode which is substantially perpendicular to a second polarization mode. The coupling device couples an input signal with an input wavelength into the optical fiber so that the input signal propagates in the first polarization mode in the optical fiber. The system for generating a pump signal generates a pump signal with a pump wavelength which is within a range of 50 nanometers (nm) to 300 nm less than the input wavelength and which has a first amount of pump power which is enough power to switch the input signal, but not enough to create higher order solitons. The coupling device also couples the pump signal into the optical fiber so that the pump signal propagates in the first polarization mode in the optical fiber.