Spin-orbital angular momentum tomography of a chiral plasmonic lens using leakage radiation microscopy.

Based on the spin-dependent directional coupling of surface plasmons (SPs) by ∧-shaped antennas, ring-shaped structures built with such antennas have potential applications for optical tweezers and optical switch technology. In this Letter, we introduce an optical method for realizing a complete polarization tomography of coupled SP fields by such a chiral-planar structure. We use a far-field optical approach, namely leakage radiation microscopy (LRM), to map the SPs propagation and polarization. Here, we fully analyze the polarization state of the generated SPs inside the vortex lens structure. In addition, we provide a theoretical model which agrees well with the experimental results.