Time-resolved broadband analysis of slow-light propagation and superluminal transmission of electromagnetic waves in three-dimensional photonic crystals

摘要

A time-resolved analysis of the amplitude and phase of THz pulses propagatingthrough three-dimensional photonic crystals is presented. Single-cycle pulsesof THz radiation allow measurements over a wide frequency range, spanning morethan an octave below, at and above the bandgap of strongly dispersive photoniccrystals. Transmission data provide evidence for slow group velocities at thephotonic band edges and for superluminal transmission at frequencies in thegap. Our experimental results are in good agreement withfinite-difference-time-domain simulations.