Induced dichroism and handedness in optical rectification

Abstract

We report on an induced circular dichroism in a structurally symmetric plasmonic array operating in the extraordinary optical transmission regime and its readout in optical rectification current, as well as in the optical transmission intensity-angle spectrum. The spin-momentum locking mechanism between the incident wave and the surface plasmon polariton (SPP) is the driving mechanism underlying the induced symmetry breaking and handedness. A great sensitivity to the sample orientation and rotation as well as to light polarization is found in the induced dichroism over certain angular ranges, along with the switching of its handedness. Analytic and computational models show that these phenomena correspond to the selective excitations of SPP resonances that can be tailored with the mesoscopic structural design for applications in vector sensing.