Abstract

We will discuss a 3-channel demultiplexer using GaAs/AlGaAs, which can separate the lightwave signals of different wavelengths. This demultiplexer utilizes the grating-assisted codirectional coupler structure [1], which can filter out the different wavelengths along the conduit waveguide (Fig. 1). Grating-assisted codirectional couplers made of two nonidentical, vertically stacked waveguides have been investigated for their use as wavelength-selective filters [2]. The center wavelength of each filtering grating section is decided by the phase-matching condition β₁−β₂ = 2π/λ, where β₁ and β₂ are the propagation constants for the two guided modes of this dualwaveguide system.

© 2003 Optical Society of America