Optical switching element between two light wave guides and optical

Abstract

An optical switching element including two parallel light wave guides, whose opposite walls are mutually separated by a small distance (d), the so-called coupling distance, each constituted by a strip of a semiconductor material formed on a semiconductor substrate having a refractive index lower than that of the guides, these guides each transporting a monomode wave and the switching being initiated by the effect of polarization means applied to the guides, characterized in that the strip constituting one of the guides (G.sub.1) designated as first guide is formed as a first uniform layer on the substrate (1), in that the strip constituting this guide is covered by a uniform intermediate layer (I) of a compatible semiconductor material, having an index lower than that of the guides and having a thickness which forms the coupling distance between the two guides, in that the strip constituting the other guide (G.sub.2) designated as second guide is formed as another uniform layer at the surface of the intermediate layer, and in that by the effect of the polarization means applied to the guides the light which is introduced into one of the guides parallel to its optical axis at a first distance from the substrate is caused to propagate through the other guide parallel to the optical axis of the latter at a second distance from the substrate, the assembly of the first guide forming with the second guide and with the intermediate layer a so-called stracked structure, whose longitudinal dimension is the coupling length.