Mode effects on supercontinuum generation from 15/130 large mode area fiber

A 15/130 Large Mode Area (LMA) fiber amplifier is constructed for super-continuum generation with a mechanical Long Period Grating (LPG) to control the transverse modes. LP₀₁ and LP₁₁ modes can be generated respectively from this amplifier. Obvious difference of supercontinuum generation between the two modes is experimentally observed, due to their different dispersion characters. Strong mode interaction is observed when exciting both of the two modes, which generates a series of new spectrum components due to intermodal nonlinear interaction, providing a way to flatten the gaps between different orders of Raman peaks so as to get a flatter supercontinuum spectrum. Supercontinuum covering the near infrared range from 800 nm to 2000 nm is obtained in this case.