Characterization of free-standing 1D photonic crystals using an effective medium approach

Photonic crystals (PCs) are usually fabricated on bulk substrates which break the symmetry of the PC system for incidence from either side of the PCs. Here we report the fabrication of a free-standing 1D layered dielectric PC by using a two-beam holographic interference method. The free-standing PC exhibits distinct photonic bandgaps as well as Fabry-Perot oscillations in the photonic bands. Furthermore, we show that the PC can be modeled by an effective medium approach and obtain the reflection phase for the photonic bands of the PC. We have also performed full-wave simulations for the PC and obtained very good agreement with the experiment. The free-standing PC enables a better comparison between experiment and simulation, and importantly, it is flexible enabling new applications for PCs.