title: Design of mid-infrared amplifiers based on fiber taper coupling to erbium-doped microspherical resonator.
abstract: A dedicated 3D numerical model based on coupled mode theory and solving the rate equations has been developed to analyse, design and optimize an optical amplifier obtained by using a tapered fiber and a Er³⁺-doped chalcogenide microsphere. The simulation model takes into account the main transitions among the erbium energy levels, the amplified spontaneous emission and the most important secondary transitions pertaining to the ion-ion interactions. The taper angle of the optical fiber and the fiber-microsphere gap have been designed to efficiently inject into the microsphere both the pump and the signal beams and to improve their spatial overlapping with the rare earth doped region. In order to reduce the computational time, a detailed investigation of the amplifier performance has been carried out by changing the number of sectors in which the doped area is partitioned. The simulation results highlight that this scheme could be useful to develop high efficiency and compact mid-infrared amplifiers.
authors.affiliation: DEE-Dipartimento di Elettrotecnica ed Elettronica, Politecnico di Bari, via E. Orabona 4, 70125 Bari - Italy. mescia@deemail.poliba.it
authors.forename: Luciano
authors.initials: L
authors.lastname: Mescia
authors.forename: Pietro
authors.initials: P
authors.lastname: Bia
authors.forename: Marco
authors.initials: M
authors.lastname: De Sario
authors.forename: Annalisa
authors.initials: A
authors.lastname: Di Tommaso
authors.forename: Francesco
authors.initials: F
authors.lastname: Prudenzano
mesh_terms: D000669:Amplifiers, Electronic; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004871:Erbium / Q000737:chemistry*; D007259:Infrared Rays; D007834:Lasers; D008027:Light; D008904:Miniaturization; D008962:Models, Theoretical; D055096:Optical Devices; D012542:Scattering, Radiation; D014159:Transducers
chemical_list: D004871:Erbium