Study of Brillouin effects in nonlinear photonic crystal fiber

Brillouin scattering spectra in a photonic crystal fiber with partially Ge-doped core is demonstrated, for the first time to our knowledge, using pump-probe technique. We have observed and characterized Brillouin spectra in the photonic crystal fiber at 1320 nm. One main peak and several sub-peaks are observed. Brillouin loss spectrum of main peak has a Lorentzian shape. The bandwidth Deltav(B) is 66 MHz and the Brillouin frequency shift v(B) is 12.054 GHz at room temperature. The peak originating from a higher order guided longitudinal acoustic mode in the graded-Ge-doped core of the photonic crystal fiber is observed for the first time. The temperature related behavior of the photonic crystal fiber is investigated. It is shown a linear dependence for the photonic crystal fiber.