High energy, single-mode, all-solid-state and tunable UV laser transmitter

Summary form only given. For flight worthy and space-qualifiable systems, compact, conductively cooled, and solid-state design configuration is vital. The technical approach for the development of a reliable, robust and efficient diode-pumped Nd:YAG pump laser is based on an oscillator/amplifier design configuration. The first stage consisted of a ring oscillator generating up to 50 mJ/pulse and dual amplifiers. The first stage generated greater than 700 m/pulse. In the second stage, amplifiers were added to obtain output energy greater than 1.2 J/pulse. The important features of this all-solid-state pump laser are as follows: (a) injection seeded ring laser that improves emission brightness (M2), (b) diode-pumped zigzag slab amplifiers that allows robust and efficient design for use in space environment, (c) advanced E-O phase modulator material that allows high frequency cavity modulation for improved stability injection seeding, (d) alignment insensitive/boresight stable 1.0 mm cavity and optical bench for achieving stable and reliable operation, (e) conduction cooled operation that eliminates circulating liquids within cavity, and (e) space-qualifiable component designs that establishes a path to a space-based mission. The goal is to obtain nearly flat-top spatial beam profile to enhance the nonlinear conversion processes used to produce the UV output wavelengths. Our approach to the oscillator head design was to develop a design that demonstrated the key features needed for a flight system and that could be easily modified for an actual flight build pump laser. To this end, we developed a design that uses a bridge structure to mount and conductively cool the zigzag slab to a pedestal on which the pump diodes are mounted. Random selection of one or more amplifiers allows obtaining different levels of output energy. This pump laser system has the potential to generate greater than 1.2 J/pulse at 100 Hz.