Direct observation of iso-frequency contour of surface modes in defective photonic crystals in real space

Direct observation of iso-frequency contours of surface modes in defective photonic crystals in real space is demonstrated in a hybrid photonic and plasmonic crystals structure with inevitable defects. The scattering process of by the randomly dispersed defects in periodic structure is analytically discussed and used to explain the reason why defects can induce direct observation of iso-frequency contour in real space. The band-structures are also obtained from the observed iso-frequency contours. The findings in this work can be useful to comprehensively characterize photonic crystals. (C) 2010 American Institute of Physics. [doi:10.1063/1.3524520]