We demonstrate a beam shaping method by engraving plasmonic lens consisted of subwavelength slit-metallic groove structure on the cleaved end facet of a composite optical fiber. The fiber consisted of a single mode optical fiber serially concatenated with a coreless silica fiber segment to expand the beam diameter. The subwavelength slit-groove structure on a gold film was fabricated using focused ion beam milling process. Plasmonic interaction in the film generated a quasi-one-dimensional Bessel-like beam with a beam width of 0.8 μm at the focal length of 2 μm. Detailed two- and three-dimensional finite-difference time-domain analyses showed beam characteristics consistent with experimental observations.
Bibliographical noteFunding Information:
This work was supported in part by the Brain Korea 21 Project, in part by the NRF grant funded by the MEST (Grant Nos. 2010-0018442, R15-2004-024-00000-0, F01-2009-000-10200-0, and 2009-00541).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)