Coupling efficiency of surface plasmon polaritons to radiation using a corrugated surface; angular dependence

The paper reports measurements on the efficiency of coupling between a surface plasmon polariton mode and radiation using a periodic corrugated surface. For surface plasmon polaritons (SPPs) propagating parallel to the Bragg vector of the corrugation, coupling efficiencies of 70%, were observed. The coupling efficiency was also measured for different SPP propagation directions relative to the corrugation and found to be high over a wide range of SPP propagation directions. These results are discussed in the context of emission from SPP-based light emitting devices.