Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Development of methods and tools for optimisation amplifying waveguide optical isolator

Once the concept of the amplifying waveguide optical isolator was demonstrated, in the frame of the ISOLASER project, improvement of the device performance could start. Four optimisation routes can be distinguished. The first one is the choice of the ferromagnetic metal (see project result no.35324). Secondly there is the development of tensile strained amplifying material with better gain performance (see project result no.35332). A third route towards optimisation is the improvement of the fabrication of the ridge waveguide isolator demonstrators. The first devices were fabricated using standard ridge waveguide laser processing, but it was directly clear that modifications were necessary to realize well-fabricated devices.

The main problem was to realize laterally monomode ridge waveguides where the ridge, and only the ridge, is entirely covered with the magneto-optic metal. The solution was to use the metal layers as the etch mask, i.e. deposit magneto-optic metal stripes on a plain wafer before defining the ridge waveguides with an etch process.

Optimising the processing parameters finally resulted in perfectly fabricated ridge waveguide isolators. The last possibility to improve the device performance is the optimisation of isolator design. At the time of designing the first devices the experimental gain-current relation of the amplifying material and the properties of the ferromagnetic metal were unknown, making the isolator design a difficult task. Furthermore, increased understanding of the component resulted in optimisation of the design strategy, focusing on the practical device specifications.

Informations connexes

Reported by