Rare earth doped confined structures for lasers and amplifiers

Abstract

Rare-earth(RE) doped insulating materiais exhibit varieties of luminescent behavior with applications in solid-state physics, high energy physics, biophysics, photochemistry, medical sciences, and telecommunications, as well as in fundamental research. Recently the incorporation of trivalent rare-earth ions into waveguides has created a considerable upsurge of interest in the field of signal processing for telecommunications, based on the success of the very efficient erbium doped fiber amplifier (EDFA) for long haul transmissions together with the explosion of Internet. Wavelengths division multiplexing (WDM) is nowadays increasing the amount of channel information over a wide energy range in the low-loss region of silica fibers. However, to cover the 25 THz available window, new materiais are required, implying the use of new doping and amplifier structures. In the course of this research, new laser sources were obtained at various wavelengths, using up-conversion pumping schemes, for instance. Furthermore, the development of RE-doped integrated optics is now considered for compactness and low-cost devices, offering a new challenge for RE-doped materiais and luminescence processes. Finally, in a promising development, extremely miniaturized devices make possible subwavelength optics that capitalize on the dynamics of a very small number of photons, which can be analyzed for example in the new RE-doped optical microcavitàes and nanostructures.