February 2016 – JGM Associates, Inc. (JGMA; Burlington, MA) has announced a patent-pending bulk-solid-state laser amplifier design having a “tailored” gain spectrum. It is based on the company’s patented diode-pumped wedged-slab (VHGM) gain module technology. In the new design, the two HR coatings that establish the zig-zag seed beam path through the VHGM slab have different center wavelengths so the two HR bands overlap only partially. The VHGM amplifier can thereby be designed to support high gain over a selected portion of the laser medium’s gain bandwidth, and anywhere within the laser medium’s gain bandwidth. In theory, the long gain lengths possible in VHGM slabs enable high amplifier stage gain even when the selected spectral portion does not include a gain peak. ASE build-up outside the selected spectrum is suppressed. The tailored-gain VHGM amplifier is expected to enable innovative laser system designs when using broad bandwidth laser gain media such as Yb-doped, Tm-doped, and Er-doped materials. New tunable and ultrashort pulse lasers may be possible. In particular, JGMA intends to develop high-pulse-energy (10-100 mJ) and high-average-power (1-100 W) ultrashort pulse MOPAs that do not employ chirped pulse amplification methods and that do not use regenerative amplifiers or pulse pickers.