Localization and channeling of light in defect modes of two-dimensional photonic crystals

The spatial distribution of the electromagnetic field in a two-dimensional photonic crystal with a lattice defect is investigated. It is shown that in such a structure the field can be localized in a region smaller than one w avelength in size. The dependence of the spectrum of defect modes on the pa rameters of a two-dimensional photonic crystal is investigated. The light f ield at the exit of the photonic crystal possesses properties of a nonradia tive mode, making it possible to achieve spatial resolution in the near-fie ld much higher than the radiation wavelength. The possibilities of using th is phenomenon in optical near-field microscopy to produce optical memory de vices and to increase the efficiency of nonlinear optical interactions are discussed. (C) 1999 American Institute of Physics. [S0021- 3640(99)00217-0] .