SBIR Phase I: Compact 1 mJ sub-hundred femtosecond fiber laser

This Small Business Innovation Research Phase I project amis to realize an all-fiber 1 mJ pulsed laser with sub-hundred femtosecond pulse duration. The laser is a chirped pulse amplification system utilizing the Raman scattering process in fiber amplifier, in order to achieve a very short pulsed laser with high energy using fiber technology. So far, it has never been demonstrated to create a parabolic Raman pulse and to compress it to a transform-limited pulse. The project will demonstrate experimentally that all-fiber system can achieve pulses with high energy and short pulse simultaneously for the first time in laser history. If successfully carried out, the results of this project will provide a breakthrough in a research for high energy short pulsed fiber lasers. Femtosecond lasers have recently drawn a paramount attraction in material processing thanks to the intrinsic high peak power. Femtosecond pulses have many advantages over the long pulses when the material processing is concerned. Whereas long pulsed lasers melt the material down, short pulsed lasers ablate material if the fluence is above the ablation threshold. Such laser ablation leaves extremely clean cut surface whereas the thermal processing leaves heat-affected morphological structure on the processed material. Hence, the femtosecond ablation is often sought for precise micro- and nano-machining. Fiber lasers are robust against the environmental changes, free from maintenance while occupying small form-factor. The proposed compact fiber lasers will fairly compete with current bulky lasers and may eventually replace them. The proposed technology will broaden the usage of femtosecond fiber lasers in the fundamental science research as well as military, aerospace, and industry.