Harmonic and single pulse operation of a Raman laser using graphene

We present an all-fiber passively mode-locked Ra-man laser using graphene as a saturable absorber. Different lengths of a highly non-linear fiber presenting normal dispersion at both pump and signal wavelengths are used in the cavity to provide Raman amplification. The cavity is pumped by a continuous wave Raman laser at 1450 nm, and generates short pulses around 1550 nm, which depending on polarization and filtering parameters can be either at the repetition rate of the cavity or at higher harmonics of it. ((c) 2012 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) ((c) 2011 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)