SBIR Phase II: Diode-Pumped, High-Power, Cr:LiSAF-Based Ultrafast Laser and THz Source

This Small Business Innovation Research (SBIR) Phase II will develop the ultrafast laser system that could represent a significant advance in the technology of directly diode-pumped, solid state, ultrafast sources. In the initial Phase I effort, a record cw power level (> 2W) from diode-pumped Lasers were demonstrated through the use of an innovative, side-pumped design. In Phase II, this design will be further improved and utilized as the basis for a regenerative amplifier to generate high peak powers. The output of a passively mode-locked, diode-pumped laser should provide the seed pulses for the regenerative amplifier. The overall ultrafast source should be simpler, smaller and ultimately less expensive than present, power-equivalent, sapphire-based ultrafast laser systems. As a demonstration of the utility of the proposed technology, a time-domain terahertz (THz) spectrometer will be constructed, based on an optical-rectification THz source and an electro-optical detector, both driven by the laser system. The directly diode-pumped ultrafast laser represents an enabling technology, allowing ultrafast and THz systems to emerge from the laboratory and into the widespread scientific and industrial applications The proposed ultrafast laser and THz spectrometer both could have the potential for significant scientific and commercial impact. With the lower cost (on the order of 50%) made possible by the simplicity of design, a wider range of research groups in academia and industry will be able to obtain ultrafast sources and THz instrumentation. The lower cost, simplicity, higher reliability and smaller size of the systems will also greatly expand and accelerate the use of ultrafast lasers and THz radiation in biotechnology, medical imaging, precision micro-machining, industrial process control and security systems.