Optical-fiber multiplexer for wavelengths of 1.3 and 0.64 mu m

A calculation, which permits formulation of the conditions for the effectiv e and stable operation of a multiplexer for 1.3- and 0.64-mu m waves using a fiber that is single-mode only at the longer wavelength, is performed in the model of a symmetric directional coupler. The conditions for efficient excitation of the fundamental mode at the shorter wavelength are considered . Isotropic and anisotropic fiber multiplexers that operate in a single-mod e regime at both wavelengths are fabricated using the analysis devised. The parameters of the multiplexers are consistent with the calculated values. (C) 2000 The Optical Society of America. [S1070-9762(00)01502-5].