ABSTRACT
We propose corrections to the coefficients in the published Sellmeier equation for stoichiometric LiTaO3 [Opt. Lett.28, 194 (2003)] that allow the extension of the wavelength range within the region of midinfrared absorption edge up to 6 microm. The required extraordinary refractive index data for this range were obtained using single-pass optical parametric fluorescence measurements with a pump wavelength of 1064.4 nm. We also observed efficient parasitic second-harmonic generation that could affect some quasi-phase-matching interactions. The corrected Sellmeier equation improves the accuracy of poling period calculations where the idler wavelength is within the region.
ABSTRACT
We propose a novel tuneable table-top optical source as an alternative to the free electron laser currently used for resonant infrared pulsed laser deposition of polymers. It is based on two-stage pulsed optical parametric amplification using MgO doped periodically poled lithium niobate crystals. Gain in excess of 10(6) in the first stage and pump depletion of 58% in the second stage were achieved when the system was pumped by a high-power Nd:YVO(4) picosecond laser source at 1064 nm and seeded by a CW tuneable diode laser at 1530 nm. An average power of 2 W was generated at 3.5 microm corresponding to 1.3 microJ pulse energy.
ABSTRACT
We describe a mode-locked, diode-pumped Nd:YVO4 laser with a very long optical cavity operating at 1064 nm. High-modulation, InGaAs quantum-well, semiconductor saturable-absorber mirrors were used for passive mode locking, providing a stable train of 13-ps pulses. A novel zero-q-transformation multipass cell provided a variable-length optical cavity as much as 100 m long. The output beam had M2 < 1.1 at average powers of 4.1, 3.9, and 3.5 W at repetition rates of 4.1, 2.6, and 1.5 MHz, respectively. To the best of our knowledge the last of these is the lowest repetition rate ever generated directly from a mode-locked nonfiber solid-state laser without cavity dumping.
ABSTRACT
We report passive mode-locking experiments with a novel self-doubling laser crystal Yb:YAl(3)(BO(3))(4) (Yb:YAB). The diode-pumped laser was mode locked by an ion-implanted semiconductor saturable absorber mirror. Far off phase matching, soliton mode locking produced pulse widths of 198 fs to 1.4 ps, with up to 660-mW output and optical efficiency of 24% at 1040 nm. The shortest pulses had a peak power of 28 kW with 440-mW average power and 16% efficiency. A few degrees off phase matching, a total of 60 mW of green femtosecond pulses was generated simultaneously. Close to phase matching, the laser produced picosecond pulses and, without infrared output, a total of 270 mW of green output, corresponding to 10% conversion efficiency (absorbed pump to green output).
