Abstract

Deep tissue imaging [1] and surgery [2] require femtosecond radiation near 1.7 μm. No direct emission at this wavelength from a mode-locked laser has been reported at the moment. However, the 1.7-μm femtosecond radiation can be generated by combining a high-energy femtosecond laser around 1.55 μm with a properly designed nonlinear frequency converter in which intrapulse Raman scattering red-shifts the spectrum of the input soliton to the targeted wavelength. Recently, high-energy femtosecond pulses were obtained with bulk optics elements which affect laser stability and increase its footprint [1]. In this communication, we report on an all-fiber format femtosecond laser with pulse energy as high as 7 nJ in the spectral window of interest.

© 2015 IEEE