Generation of compact radially polarized beam at 850 nm in vertical-cavity surface-emitting laser via plasmonic modulation

We propose a convenient approach for generating compact radially polarized laser beam by integrating concentric gold rings on the surface of a vertical-cavity surface-emitting laser. Due to the polarization selection of the surface plasmon polariton mode excited by the gold rings, a radially polarized beam at 850 nm is experimentally demonstrated. The physical mechanisms of the generation are numerically and analytically analyzed by employing finite-difference time-domain method and metal-insulator-metal plasmonic waveguide theory. (C) 2010 American Institute of Physics. [doi:10.1063/1.3518065]