Z. Cheng

Toward a terawatt-scale sub-10-fs laser technology

Powerful techniques for spectral broadening and ultrabroad-band dispersion control, which allow compression of high-energy femtosecond pulses to a duration of a few optical cycles, are analyzed. Spectral broadening in a gas-filled hollow fiber and compression by chirped mirrors with high-energy 20-fs input pulses are presented. Using 1-mJ seed pulses we have demonstrated the generation of 0.5-mJ 5-fs pulses at 0.8-/spl mu/m and 1-kHz repetition rate. General design criteria to scale the compression technique toward the terawatt level are presented.

Compression of 2 mJ kilohertz laser pulses to 17.5 fs by pairing double-prism compressor: analysis and performance

A general expression of dispersion for pairing double-prism compressor with arbitrary apex angle is presented and a limitation to generate negative group-delay dispersion (GDD) for broadband spectrum is obtained. By use of this compressor with spectral shaping filters and chirped mirrors, 2 mJ, 17.5 fs pulses from a compact 10-pass kilohertz Ti:sapphire amplifier system are generated.

Routes to fiber delivery of ultra-short laser pulses in the 25 fs regime

Femtosecond laser pulses came of age and found applications in many fields of life-sciences that call for dispersion-managed guiding of very short optical pulses. We investigate the potential for delivering 25-fs, nanojoule pulses from a Ti:Sapphire laser through optical fibers with lengths of up to 2m.

Tabletop generation of carrier envelope phase stabilized multi-mJ few-cycle pulses

A compact system for the generation of few-cycle multi-mJ carrier envelope phase (CEP) stabilized pulses is presented. The output 5.4 fs, 1.9 mJ pulses have CEP noise of only 190 mrad rms over seven hours.

Amplification of femtosecond laser pulses beyond the gain narrowing limit

Summary form only given. Titanium:sapphire based oscillator-amplifier systems employing chirped-pulse amplification techniques are useful for compact table-top sources of high-intensity optical pulses. We propose a scheme in which efficient spectral broadening of the pulses will take place in the first few passes of the amplifier. To avoid damage we will substantially stretch the pulses before the last few passes in the first amplifier stage. Residual phase errors will be compensated by newly designed broadband chirped mirrors or/and by the acousto optic programmable dispersive filter (AOPDF). We will present a detailed comparison of the performance for the different employed phase and amplitude shaping devices. Special emphasis is put on the characterization of the spectral phase of the output pulses, the pulse contrast and the beam profile. Based on these investigations we will set up an amplifier system capable of generating intense sub-15 fs laser pulses.

Compression of high energy femtosecond pulses by the hollow fiber technique: Generation of sub-5-fs multigigawatt pulses

Powerful techniques for spectral broadening and ultrabroad-band dispersion control, which allow compression of high energy femtosecond pulses to duration of a few optical cycles, are presented. Spectral broadening by propagation along hollow fiber filled with noble gases is studied under two excitation regimes with high energy input pulses of 140-fs and 20-fs duration respectively. With 20-fs input pulses and under optimum compression conditions we show a pulse shortening down to 4.5 fs with output energy up to 70 μJ using a high throughput prism-chirped mirror delay line.

Generation and Application of Subterawatt 5-fs Optical Pulses

We report on the generation and application of 5-fs pulses at the subterawatt peak power level. A compact all-solid-state femtosecond Ti:sapphire oscillator-amplifier system produces 20-fs, 1.5-mJ pulses. The pulses are subsequently compressed in a hollow-fiber-chirped-mirror compressor. The system delivers bandwidth-limited 5-fs, 0,5-mJ pulses at 780 nm in a diffraction-limited beam. These pulses have been used to investigate the optical damage in dielectrics and the generation of high harmonics in gases down to the water window.

Pulse Compression To Sub-5 fs At Multigigawatt Peak Power

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