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Continuous-wave laser operation at 1060.2 nm was demonstrated in polymer channel waveguides doped with a Nd complex above an absorbed pump threshold of 50 mW. The highest slope efficiency of 2.15% was obtained with 5% outcoupling, resulting in a maximum output power of 0.98 mW. Lasing was also achieved on the quasi-three-level 878 nm transition above a threshold of 74.5 mW. A slope efficiency of 0.35% and an output power of 190 microm were obtained with 2.2% outcoupling. Long-term, stable cw laser operation over at least 2 h was demonstrated, indicating the durability of the polymer gain medium.

A novel technique for the laser-induced forward transfer (LIFT) of material in solid phase from a thin film precursor is presented. Multiple, sub-threshold energy femtosecond pulses are used to lessen the adhesion of a donor film to a support substrate to facilitate forward transfer of solid 'pellets' of donor material to a receiver. A relatively higher intensity outer ring is added to the transfer laser pulses, by means of the near-field diffraction pattern of a circular aperture, to define the area for transfer in the donor film and allow for more reproducible pellet shapes. This technique has been termed Ballistic Laser-Assisted Solid Transfer (BLAST).

This paper documents the lasing performance of a waveguiding layer of Ti:sapphire, of ~12µm thickness, grown by pulsed laser deposition from a 0.12 wt % Ti2O3 Ti:sapphire single crystal target onto an undoped z-cut sapphire substrate. Lasing around 800nm is observed, when the waveguide layer is pumped by an argon ion laser, running on all blue green lines, with an absorbed power threshold of 0.56W using high reflectivity (R>98%) mirrors. Using a 5% pump duty cycle and a T = 35% output coupler, a slope efficiency of 26% with respect to absorbed power is obtained, giving quasi-CW output powers in excess of 350mW.