Dynamic generation of plasmonic Moiré fringes using a phase engineered optical vortex (OV) beam is experimentally demonstrated. Owing to the unique helical phase carried by an OV beam, the initial phase of surface plasmon polaritons (SPPs) emanating from a metallic grating can be adjusted dynamically by changing the phase hologram displayed on a spatial light modulator. Plasmonic Moiré fringes are readily achieved by overlapping two SPP standing waves with certain angular misalignment, excited by the positive and negative topological charge components, respectively, of a cogwheel-like OV beam. The near-field scanning optical microscopy measurement result of SPP distributions has shown a good agreement with the numerical predictions.
© 2012 Optical Society of America
Optics at Surfaces
Original Manuscript: April 10, 2012
Revised Manuscript: May 17, 2012
Manuscript Accepted: May 17, 2012
Published: June 26, 2012
Guanghui Yuan, Qian Wang, and Xiaocong Yuan, "Dynamic generation of plasmonic Moiré fringes using phase-engineered optical vortex beam," Opt. Lett. 37, 2715-2717 (2012)