A perfect plasmonic quarter-wave plate

The excitation of surface plasmons on an elliptical grating followed by the transmission through a subwavelength aperture can modify the polarization state of the incoming light. The combined effect of the elliptical grooves and a slightly elliptical central hole allows to fully control the birefringence and retardation of the structure, providing a simple approach for polarization state design by the geometry of the structure. From this combination, a perfect plasmonic quarter-wave plate is obtained. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4766189]