Investigação teórica de um laser de fibra óptica de sílica dopada com íons de itérbio de alta potência bombeado por diodos Laser para aplicações industriais.

Abstract

In this work, a theoretical model based on the density matrix formulation for the complex electric susceptibility of the two-photon problem (laser absorption and emission) was devel- oped. Additionally, starting from the general equation of electromagnetic fields, as well as the pumping and laser signals, interacting with the three-level quantum system formed by an ensemble of ytterbium atoms (Y b+3 ), a simplified model was developed. This model allows coupling the rate equations with the thermal dinamics, considering the heat removal from the optical fiber. The developed models were applied to the study of high-power ytterbium-doped double-clad optical fiber lasers (YDCFL) operating in continuous wave (CW ) mode at kilowatts power levels, at a wavelength of λs = 1018 nm. The obtained results are relevant for the construction of high-power fiber lasers pumped by 976 nm diode lasers. A semiclassical approach was adopted for describing the laser emission phenomenon. In this perspective, the quantum system was described by the Schrödinger equation of quantum mechanics, while the classical system was treated by Maxwell’s equations.