Influences of temporal dispersion and nonlinear absorption on discrete interface solitons in hetero-structure waveguide arrays

A theory is presented to investigate the formation of unstaggered and staggered (or Tamm) discrete interface solitons via the Kerr effect in hetero-structure waveguide arrays. The influences of temporal dispersion and nonlinear absorption are discussed in detail for different initial pulse power levels. It is shown that an unstaggered. soliton with low power is destroyed by normal dispersion while a high power unstaggered soliton can propagate, keeping the intensity profiles, although an energy loss is evident. For a staggered soliton with moderate or high input power, the nonlinear absorption causes substantial energy loss, while the normal dispersion breaks the input pulse into a train of short and high peak pulses, localized within the central waveguide. We also investigate the influences of anomalous dispersion on staggered solitons, and find that it would be better if the wavelength of the light is set at the anomalous dispersion region to excite these staggered solitons.