Compound spin Hall plasmonic lens

Abstract

The propagation phase and the Pancharatnam–Berry phase are two primary strategies to control surface plasmon polaritons (SPPs) wave, however, hampered by the spatial conjugation and the spin conjugation, respectively. Combining these two approaches together, the conjugations are broken and a compound spin Hall plasmonic lens (SHPL) is proposed and demonstrated numerically and experimentally in the visible frequency range. The proposed strategy can be utilized to realize both transversal and longitudinal deviations of SPP focus. The positions of the SPP focus can be dynamically modulated by switching the spin states of excitation light and adjusting the phase gradient encoded onto the lens. Promising applications of the proposed SHPL include on-chip communication and polarization detection.