Estimation of photonic band gap in silicon crystal waveguide through acousto-optic interaction

Abstract

The photonic band gap through acousto-optic interaction in a face-centred cubic silicon crystal is theoretically studied. The dispersion relation for acoustic wave is obtained using method of potentials with boundary conditions involving the bulk and surface stress of considered materials. The dispersion relation for optical wave is derived by transfer matrix method and boundary conditions based on electromagnetic theory. Observation shows that the central frequency of photonic band gap in silicon crystal can be chosen in any desired infrared optical frequency range by adjusting the frequency of acoustic wave. Also, the size of these band gaps in chosen optical frequency range can be further tuned through incident angle of light wave. This study may provide an efficient method to obtain tuneable photonic crystal. © Springer Science+Business Media New York 2015.