Brillouin scattering property in highly nonlinear photonic crystal fiber with hybrid-core structure

Brillouin scattering property of a highly nonlinear photonic crystal fiber with hybrid-core structure is studied. It is shown that there exist five Brillouin resonance peaks in two groups. These peaks have similarly linear dispersion characteristics and their effective acoustic velocities increase monotonically by the order of the peaks. The acousto-optic overlapping efficiency in the fiber is experimentally measured to be ∼50-%. Temperature and strain dependences of the first resonance peak are also investigated.