Surface plasmon polariton discrete diffraction compensation.

We report on the observation of discrete diffraction in surface plasmon polariton waveguide arrays at a wavelength of 1550 nm. We also adopt the effective index method to reduce our simulation geometry to two-dimensions, predict the spread of single-waveguide excitation in parallel waveguide arrays, and explore changing the excitation angle to detune the waveguides. Our experimental results show discrete diffraction compensation at an angle of 2.2 degrees as predicted by simulations.