Rare-earth doped chalcogenide optical waveguide in near and mid-IR for optical potential application
Résumé
Mid-infrared (IR) emissions are motivating for a variety of applications including environmental sensing, LIDAR and military counter-measures. In this research field, halcogenide fi bres as host materials for rare earth ions can play a major part. Moreover, the fabrication of amplifying integrated optical structures is of great interest in the fi eld of modern telecommunication technologies or optical sensing. These optical components can be applied to compensate waveguide losses, coupling and splitting losses, as well as to fabricate integrated laser sources, operating in the telecom bands or middle IR. With high refractive index values and an appropriate rare-earth (RE) solubility, chalcogenide glasses exhibit high spontaneous emission probabilities and, consequently large emission cross-sections for radiative electronic transitions of RE3+ ions. The low phonon energy of these materials (~ 350 cm-1 for sulphides and ~ 250 cm-1 for selenides) limits the non-radiative multiphonon relaxation rates. All these properties result in high quantum effi ciencies for rare earth ion transitions in chalcogenide glasses. However, infrared emissions beyond 3 μm originating from rare earth ion doped amorphous chalcogenide fi bres or planar waveguide are reported more rarely. The development of the Er3+ and Dy3+-doped sulphide and selenide fi bres and sputtered fi lms will be described focusing on their relevant compositional, structural and optical characteristics.