An expression is derived for the intensity-dependent index of refraction of a rare-earth-doped fiber laser by use of a Kramers–Kronig relation and simple rate equations. The solution is applied to examine the properties of the nonlinear index of an ytterbium-doped silicate fiber laser at 975-nm pump and 1080-nm laser wavelengths.
© 2004 Optical Society of America
Erik Bochove, "Nonlinear refractive index of a rare-earth-doped fiber laser," Opt. Lett. 29, 2414-2416 (2004)