Ultrashort light pulses in photonic crystals in subdiffractive regimes

We investigate analytically (by harmonic mode expansion) and numerically (by finite-difference-time-domain technique) the propagation of light pulses in photonic crystals in subdiffractive regimes. It is shown that in general the short pulses of narrow beams diffract more strongly than the corresponding monochromatic beams and disperse more strongly than the corresponding pulses of the plane waves. We also demonstrate coupling between the temporal dispersion and the spatial dispersion (diffraction) resulting in a complicated spatiotemporal evolution of the propagating pulses. (c) 2007 Optical Society of America.