LASER SPECTROSCOPY OF RARE-EARTH-DOPED GLASS WAVE-GUIDES

A brief review is presented of rare earth-doped glass waveguides and their applications to optical telecommunication systems or other potential devices. Attention is focused on a few fundamental questions, such as the inhomogeneous broadening of the linewidth and upconversion mechanisms, which are relevant for applications as broad-band amplifiers and visible upconversion pumped lasers respectively. Conclusions are drawn with regard to new planar waveguides and their optical properties.