Excitation control of long-range surface plasmons by two incident beams.

We demonstrate the excitation control of long-range surface plasmon polaritons (LRSPs) by experiments and simulations. We find that LRSPs and short-range surface plasmon polaritons can be selectively excited by two incident beams. This mechanism enables us to realize the excitation control of LRSPs using the phase difference or the intensity ratio between the two input signals. The excitation method analyzed here can be applied to active plasmonic devices based on LRSPs.