Plasmon-enhanced nonlinear yield in the Otto and Kretschmann configurations

Propagating surface plasmons in the laboratory can have basic properties quite different from those of the ideal surface plasmon polariton, which is a bound mode at the interface between two infinite media. Features such as field confinement and propagation length are affected by the configuration used for coupling to the far field. We experimentally investigate how the Otto and Kretschmann configurations influence the linear coupling properties of smooth metal layers and the nonlinear generation of the second harmonic. The results are compared to calculations from electrodynamic theory based on the hydrodynamic model, which confirm that the nonlinear yield is an order of magnitude greater in the Kretschmann configuration than in the Otto configuration.