We demonstrate a simple method for plasmon surface polariton coupling. A dielectric layer sinusoidally modulated in height (dielectric grating) on top of a metal layer is used as the dispersive element for the momentum coupling between the incoming photon and the plasmon surface polariton. Hence, no modulation of the metal surface is necessary. This coupling method is used to study the thermal decomposition of dielectric gratings. ©1997 American Institute of Physics.