Large Aperture OP-GaAs for High Power Frequency Conversion (only of SF424)

Laser systems with high peak power, average power, and repetition rate, along with short pulse lengths are needed to perform scientific experiments in which they are synchronized with DOE funded accelerators. One of the key components of such laser systems, nonlinear optical crystal used to generate radiation with the desired properties, is in its present form not able to survive under the conditions needed to meet the application requirements of DOE accelerator facilities. • General statement of how this problem is being addressed. Physical Sciences Inc. (PSI) proposes to solve this problem by developing a practical process for manufacturing orientation-patterned gallium arsenide (OP-GaAs) with a thickness of up to 10 mm. PSI’s existing manufacturing process, which has already produced QPM devices with a thickness of 1 mm, will be appropriately modified to enable scaling to larger thicknesses and thus to larger power-handling capabilities. • What is to be done in Phase I? During Phase I a key processing step needed to scale up the thickness, wafer bonding will be developed. Optical crystals will be fabricated from the bonded wafers, and their power-handling capabilities will be tested. Polishing of OP-GaAs devices, a necessary prelude to bonding them together, will be demonstrated. • Commercial Applications and Other Benefits. The DOE operates a network of accelerator facilities which can benefit from the development of tunable lasers systems with high average power and high peak power. These laser systems can be used for pump/probe experiments in which pulses of light from the laser are synchronized with pulses of light created by the accelerator. The proposed project will lead to the creation of a domestic manufacturing capability for one key optical component of high-average power laser systems for accelerator research. This optical component will also find application as a component of defense systems requiring high average power in the mid-infrared: next-generation countermeasures for aircraft defense, long-range imaging and targeting, and directed-energy weapons. • Key Words: accelerator-based pump-probe experiments, ultrafast lasers, optical parametric chirped pulse amplification, quasi-phasematching, orientation-patterned gallium arsenide