A terawatt KrF/Ti:sapphire hybrid laser system with a high contrast be
tween amplified spontaneous emission and the main pulses has been deve
loped with an output energy of 130 mJ in 130-fs pulses. An efficient f
requency-tripling scheme with Ti:sapphire is demonstrated with an effi
ciency of 11% in the 100-fs regime with LiB3O5 and beta-BaB2O4.