Optical fiber amplifier doped with dysprosium ion for the 1.3 amp;mgr;m wavelength band

摘要

A core of a fluorozirconate optical fiber is doped with rare earth ions, namely trivalent Dy ions. The Dy ion makes an absorption transition with excitation light generated by an 800 nm semiconductor laser module. Then the Dy ion undergoes transitions, namely a nonradiative transition involving phonon emission, a transition to a metastable excited level, and a radiative transition wherein radiation corresponding to the 1.28 . mu.m to 1.35 &mgr;m range occurs, thereafter returning to its ground state level. The Dy ion having an electrovalence of three can be pumped with a high-output 800 nm semiconductor laser module and is not subject to saturation at a lower energy level of population inversion. Using an optical fiber of the invention, a higher gain is obtained in the region of 1.3 &mgr;m telecommunications window.