Microcavities in photonic crystals: Mode symmetry, tunability, and coupling efficiency

We investigate the properties of resonant modes which arise from the introduction of local defects in two-dimensional (2D) and 3D photonic crystals. We show that the properties of these modes can be controlled by simply changing the nature and size of the defects. We compute the frequency, polarization, symmetry, and field distribution of the resonant modes by solving Maxwell's equations in the frequency domain. The dynamic behavior of the modes is determined by using a finite-difference time-domain method which allows us to compute the coupling efficiency and the losses in the microcavity. 1996 The American Physical Society.