Abstracts

In this thesis it is shown that cw pumping of aKerr lens modelocked Ti:Sapphire laser is not restricted to argonlasers but can be achieved with an arc lamp-pumped, intracavityfrequency-doubled, cw Nd:YLF laser without reduction of Ti:Sapphirelaser output quality. A Nd:YLF laser was designed and constructedfor this purpose, and modelocked operation of a Ti:Sapphire laserdemonstrated. The design of the Nd:YLF laser involved optimizationof beam size for maximum energy extraction from the amplifyingmedium and for intracavity frequency doubling. The design alsoachieved mechanical stability for low amplitude noise in thefundamental and minimized the generation of noise caused by modecoupling during the frequency doubling process, referred to as the"green problem". Noncritically phase matched LBO was used forsecond harmonic generation. A total of 7W second harmonic power anda conversion efficiency of 52% have been achieved. Noise levels(peak to peak) of below 1% around ~500Hz in the fundamental andbelow 5% around 10-200Hz in the second harmonic were achieved.Damage to the anti-reflection coating on the LBO crystal, caused bythermal expansion of the LBO, severely limited output performancesduring prolonged operation.
A Ti:Sapphirelaser, pumped with the output of the Nd:YLF, showed a threshold of1.8W for modelocked operation and ~1.0W for continuousoperation.