Compact all-solid-state laser emits 5-fs, 0.1-TW pulses at a repetition rate of 1 kHz

Compact all-solid-state laser emits 5-fs, 0.1-TW pulses at a repetition rate of 1 kHz

An all-solid-state Ti:sapphire oscillator/amplifier with a hollow-fiber/chirped-mirror pulse compressor that produces 5-fs pulses with peak powers of 0.1 TW at a 1-kH¥repetition rate was described by scientists from the University of Technology (Vienna, Austria) and the Research Institute for Solid State Physics (Budapest, Hungary) in CLEO `97 paper #CPD5. The researchers believe this is the first such system operating without a grating-based pulse compressor and with a single pum¥source for the amplifier and a single amplifier stage.

Pumped by a diode-pumped Nd:YVO4 laser, the Kerr-lens-modelocked, mirror-dispersion-controlled Ti:sapphire system produced sub-10-fs seed pulses at 780 nm. Propagation of the beam through SF57 glass (Schott Inc.; Duryea, PA)--and isolation and pulse selection components--broadened the pulses by a factor of more than 1000. A multipass amplifier boosted the gain by nearly six orders of magnitude, producing pulses with energies between 1.2 and 1.4 mJ. A hollow glass fiber filled with argon gas at 1 bar spectrally broadened the pulses by self-phase modulation (see Laser Focus World, May 1997, p. 127). Ultrabroadband chirped dielectric mirrors compressed pulses in five reflections; design improvements over earlier versions yielded nearly constant negative group-delay dispersion from 650 to 950 nm. The setu¥produced 0.5-mJ, 5-fs pulses at 1 kH¥with 1-mJ, 20-fs seed pulses. Preliminary studies suggest that the system could drive kilohertz-rate coherent extreme-ultraviolet sources.