Fibre Raman laser directly pumped by multimode laser diode at 975 nm

Summary form only given. Fibre Raman lasers (FRLs) offer a number of attractive properties such as wavelength agility, immunity to photodarkening even at short wavelengths, absence of energy storage, and instantaneous gain [1]. Here, we report what we believe is the first continuous wave (CW) FRL pumped directly by a multimode diode laser. This is particularly attractive for power-scaling, efficiency, and short-wavelength operation. We reached a slope efficiency of 55% with respect to launched pump power and an output power of 4 W at an emission wavelength of 1019 nm.