Optical frequency mixing at coupled gold nanoparticles.

摘要: We present nonlinear-optical four-wave mixing (4WM) at coupled gold nanoparticles. By decreasing the interparticle distance from large separation to touching contact, 4WM yield increases by 4 orders of magnitude. The reason for this dramatic enhancement lies in shift localized plasmon resonance infrared wavelengths as dimer is formed, making one input doubly resonant. At point, signal changes discontinuously because a sudden charge redistribution imposed formation conductive bridge. 4-wave provides an ultrasensitive measure contact point between pair particles and it can be employed spatially temporally controllable photon source.