Near field experiments and theoretical modeling on visible photonic bandgap structures

Abstract

Summary form only give. We have obtained preliminary theoretical and experimental results on a visible photonic band gap (PBG) structures which consists of 20 rows of 146 nm air pores arranged in a triangular lattice with pitch of 260 nm etched into the center of a planar waveguide. The waveguide has a thermally grown 1.8 /spl mu/m thick silicon dioxide substrate buffer, followed by 250 nm thick silicon nitride waveguiding layer and a thin 75 nm silicon dioxide cladding layer. Near field scanning optical microscopy (NSOM) is employed to probe the PBG structures. NSOM achieves its subdiffraction spatial resolution by scanning an aperture of /spl sim/100 nm at a distance of /spl sim/10 nm above the surface of interest; thus NSOM can provide details of local photon density of states and mode structure as light propagates through both the planar region and PBG stripe.