Stretcherless, Femtosecond mJ Fiber Amplifier with Coherent Pulse Stacking

We propose to combine a strecherless fiber amplification technique developed by KMLabs that produces sub-200 fs, 0.1 mJ-class pulses with a coherent pulse stacking technique developed at the University of Michigan to obtain mJ-class, femtosecond output pulses without relying on traditional chirped-pulse-ampltification. The coherent pulse stacking technique coherently adds multiple lower-energy pulses together and has been demonstrated up to enhancement factors of 9x with a clear path to enhancement of greater than 80x. Such a source would provide high energy, ultra short pulse pulses from a fiber laser platform without the disadvantages of bulky diffraction-grating stretcher and compressors. This advancement would further ruggedize high-energy ultrashort pulse laser devices for mobile deployment as well as opening scientific and commercial applications that have traditionally relied on amplification in bulk laser media because of the pulse energy and pulse duration limitations of fiber lasers.