Probing photonic Bloch wavefunctions with plasmon-coupled leakage radiation

We demonstrate theoretically and experimentally the direct observation of photonic Bloch wavefunctions in dielectric loaded plasmonic crystals. The ultimate ability to observe the Bloch wavefunctions in the surface emission images depends not on the light diffraction through the holes but on the strength of the in-plane light scattering from the individual lattice features and the presence of the metal layer which allows the light propagating within the crystal to be imaged in the far-field. Experimental results are in excellent agreement with simulated surface emission and back focal plane images of plasmonic crystals.