Er/Tm:fiber laser system for coherent Raman microscopy.

We present a novel architecture for a fiber-based hybrid laser system for coherent Raman microscopy, combining an amplified Er:fiber femtosecond oscillator with a Tm:fiber amplifier boosting the power of the 2-μm portion of a supercontinuum up to 300 mW. This is enough to obtain, by means of nonlinear spectral compression, sub-20-cm(-1) wide pump and Stokes pulses with 2500-3300  cm(-1) frequency detuning and average power at the 100-mW level. Application of this system to stimulated Raman scattering microscopy is discussed.