title: Grating-free nth order cascaded Raman fibre lasers using highly Ge-doped low loss fibre.
abstract: Pumped by a narrow band Nd(3+)-doped fibre laser, a grating-free three-wavelength Raman fibre laser has been demonstrated. More than 1.3W output power at the third Stokes line of 1230 nm, a bandwidth of 1.8nm and a slope efficiency of ~28% was measured. A four-wavelength Raman fibre laser was also demonstrated using a different resonator that consisted of a 4% fibre end reflector, a dielectric mirror and a single fibre Bragg grating. This method is simple, versatile and cheap compared with conventional methods employing fibre Bragg gratings used to resonate all Stokes wavelengths.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Zhao
authors.forename: Yahua
authors.initials: Y
authors.lastname: Li
authors.forename: Stuart
authors.initials: S
authors.lastname: Jackson