Theoretical And Experimental Research On New Wavelength2μm Fiber Lasers

New wavelength2μm Tm3+-doped fiber laser and Tm3+-Ho3+codoped fiber laseroperate in the eye-safe wavelength spectral region, they haave a large tunable wavelengthrange from1.8μm to2.1μm, and can be efficiently pumped by790nm、1212nm or1580nmpump sources. They are powerful tools in the laser medical field for owning advantages ofboth Nd3+:YAG laser and CO2laser, and have various applications in remote sensing、ladarand space optical communication, besides，they can be used to generate3μm-5μmmid-infrared sources.The major works of this thesis are shown as follows:（1） Starting from the energy levels、absorption and emission spectra of doped ions, weintroduce the fundamental principle of2μm fiber laser, and establish the mathematicaltheory models for³H₆�'³H₄,³H₆�'³H₅,³H₆�'³F₄three kinds of pump methods usingthe rate equation theory.（2） Adopting Matlab software, we do numerical simulation for³H₆�'³F₄pumpmethod, and we get the distribution of pump power and signal power in the fiber for the2μm Tm3+-doped fiber laser and Tm³⁺-Ho³⁺codoped fiber laser, and analyze the influences offiber length and doping concentration on the performance of2μm fiber laser.（3） We set up a1570nm dual amplification pump system with the maximum outputpower of about800mW, which is used to pump a linear cavity Tm-doped fiber laser and aring cavity Tm-Ho codoped fiber laser, and we get laser output with the center wavelength ofabout1990nm for the former one, as for the latter one, we get1855nm laser output withspectral linewidth of about4nm, SMSR of about30dB, the maximum output power of about60mW and the slope efficiency of about12%as for the launched pump power.