Miniature Gain-Switched Lasers*

Compact supercontinuum source for the visible using gain-switched Ti:Sapphire laser as pump

“…In this paper we demonstrate a compact supercontinuum source for visible wavelengths that is based on pumping a highly nonlinear, off-the-shelf microstructured optical fiber with a miniature gain-switched Ti:Sapphire laser. The pump laser is similar to the devices demonstrated by Zayhowski et al [13,14]. It produces broadband nanosecond pulses at 780 nm which, when coupled into to the fiber, generate a smooth supercontinuum covering the wavelengths from 410 nm to 1300 nm.…”

“…The intense pumping creates a high population inversion, which is released in the form of a short output pulse. For visible SC generation, an interesting alternative is to use Ti:Sapphire as the gain-switched laser medium and pump it by a frequencydoubled Q-switched Nd:YAG laser [13,14]. Such a laser can be made compact and passively cooled, and its output wavelength can be tuned over a large range because of the extremely broad gain in the Ti:Sapphire crystal [15].…”

Broadly tunable ultraviolet miniature cerium-doped LiLuF lasers

“…When the pump energy is close to the threshold, the laser output quickly increases with pump pulse energy due to a rapid decrease of the build-up time of the Ce:LiLuF laser pulse, allowing earlier extraction of the population inversion and consequent reduction of the losses from fluorescence decay. This effect is typical for gain-switched laser systems [12]. The slope of the curve for higher pump powers, for which the build-up time of the cavity is reduced to much less than the crystal upper level life time (45 ns for Ce:LiLuF), gives a true indication of the slope efficiency of the laser.…”

Passively Q-switched microchip laser at 15 μm

“…1,2 Gain switching of a Cr 4ϩ :YAG laser pumped with a Q-switched Nd:YAG microchip laser was demonstrated recently. 3 A more direct, simple, and efficient approach is passive Q switching of a 1.5-m laser with an absorber crystal (e.g., Co 2ϩ :LaMgAl 11 O 19 , 4,5 Er:Ca 5 (PO 4 ) 3 F, 6 U 4ϩ :CaF 2 , 7,8 U 4ϩ :SrF 2 , 9 Co 2ϩ :ZnSe, 10 Cr 2ϩ :ZnSe 11 ) or with a semiconductor saturable absorber mirror (SESAM). 12 Laser emission at ϳ1.5 m has been reported from several gain materials including Cr 4ϩ :YAG (review on Cr 4ϩ -doped garnets), 13 Yb 3ϩ :Tm 3ϩ :YLiF 4 , 14 Er:Ti:LiNbO 3 , 15 and, most commonly used for diodepumped bulk lasers, Er:Yb:glass.…”