'HE INE 'LUENC PLASMON-INDUCED TUNNE' T

The interaction of propaga ice plasm excited in a silver film with the tunneling junc scanning 5 micros- cope has been investigated. Under particular condilionb wa rluu a strong plasmon-induced current (PIC) superimposed on the tunneling current. The generation of the PIC is in our view due to the rectification of the optical electric field by the nonlinearity of thp tunneling junction. To ob- tain a PIC with detectable r 3 an enhancement of the optical field between tip and sample by rders of magnitude is required. The observed dependence of the