As. Kurkov et al., Highly efficient cladding-pumped fibre laser based on an ytterbium-doped optical fibre and a fibre Bragg grating, QUANTUM EL, 29(6), 1999, pp. 516-517
Ytterbium-ion-doped double-clad optical fibres were developed, The differen
tial quantum efficiency of a diode-pumped fibre laser, fabricated on the ba
sis of such optical fibres with a fibre Bragg grating, was 90%.