Fabrication and Characterization of Monolithically Fused Wavelength-Independent 1 × 4 Couplers

Abstract

A new method for the fabrication of a monolithic 1 4 single-mode fused coupler is described together with details of its performance in terms of coupling ratio, spectral response and polarization sensitivity. The fabricated device exhibits ultra-broadband performance with low polarization dependent loss. The coupling pattern exhibits identical coupling to all interacting fibers, enabling an easy control on fabrication parameters of the device.