2.8-fs clean single transform-limited optical-pulse generation and characterization

Generation of 0.5 mJ, few-cycle laser pulses by an adaptive phase modulator

“…In our experiments, since the GDD of white light φ "(ω) is large, φ 0 "(ω)=500fs 2 was added on the SLM to pre-compensate the phase before the first iteration. The linear component of φ 0 (ω) was chosen such that the phase load per pixel was minimized [24]. The first iteration of the MIIPS pattern is shown in Fig.…”

Angularly-dispersed optical parametric amplification of optical pulses with one-octave bandwidth toward monocycle regime

“…The negative GDD added by SLM for chirped pulse amplification was about -550 fs 2 . This value slightly exceeds typical limitation (-400 fs 2 ) for our 4-f system, which depends on "load per pixel" [21]. Too much load not only decreases the accuracy of pulse compression, but also causes the intensity modulation by diffraction on SLM.…”

“…We let the split beam (300 μJ/pulse) of the output from a cryogenically-cooled Ti:sapphire laser amplifier system (Red dragon II, KMLabs inc., a pulse duration of 25 fs, a center wavelength of 786 nm, a repetition rate of 1 kHz) propagate in a hollow fiber (a length l of 370 mm, an inner diameter d of 0.1 mm) which was set in a chamber filled with 3.0-atm argon gas. Ultrabroad-band pulses generated by SPM in the noble gas were guided into a grating-based 4-f pulse shaper with a liquid crystal spatial light modulator (SLM, a pixel number of 648, a transmission range of 400 -1300 nm, a pixel size of 102 μm) [14,15,21], and subsequently into the A-NOPA system as down-chirped seed pulses (a pulse energy of ∼0.5 μJ, a spectrum from 500 to 1100 nm, a pulse duration of ∼ 300 fs), as shown in Fig. 4.…”

“…Our hollow fiber technique does not need a high OPA gain so that we can suppress the superflueorescence in the gain medium. In addition, we have already succeeded in compensating for the chirp of the output from a hollow fiber almost completely [15,21]. The low throughput of our 4-f system which was used for the nonlinear chirp compensation [18] is not a problem because lost pulse energy will be easily recovered by an A-NOPA system.…”