Intermodal stimulated Brillouin scattering in two-mode fibers

Characterization of stimulated Brillouin scattering (SBS) in an elliptic-core two-mode fiber is experimentally demonstrated. The LP01 or LP11 mode is selectively launched to a fiber under test by a mode-selective coupler as a Brillouin pump, and the Brillouin gain spectra are analyzed for different mode pairs of the pump and probe waves. Intermodal SBS between counterpropagating LP01 and LP11 modes is observed, and the efficiency is measured to be about 58% of that of the SBS between the LP01 modes. (C) 2013 Optical Society of America