Heavy photon dispersions in photonic crystal waveguides

Heavy photon dispersion curves exhibiting group velocities suppressed by tw o orders of magnitude are measured directly for deeply etched AlGaAs wavegu ide structures by means of surface coupling techniques. It is shown that du e to the wave vector-selective nature of surface coupling, such techniques permit the excitation of modes of specific, known dispersion in photonic cr ystal waveguides. Coupling to regions of very strong anomalous dispersion i s demonstrated, with potential to be developed into a method for excitation of gap solitons. (C) 2000 American Institute of Physics. [S0003-6951(00)04 728-8].