New effects in an ultracompact Young's double nanoslit with plasmon hybridization

We present a theoretical study on the anomalous transmission of an asymmetric Young’s double metallic nanoslit with an ultrathin interval. The slit–slit interactions show exotic optical properties, particularly strong suppression of light transmission with narrow bandwidth and red/blue shifting of transmission peaks from individual slits, in contrast to currently welldeveloped subwavelength optical structures. Dip transmission is also observed to gradually decay with increasing interval distance. Analysis results reveal that such a phenomenon physically lies in the hybridized cross-talking of surface modes within two slits throughout the interval film in between. Depending on the plasmon hybridization type, either symmetric or antisymmetric, the newly induced optical phase retardation between the two slits can decrease and increase, respectively. This investigation suggests a potential way of nonlinearly bonding metallic waveguides and consequently aiding in the design of new plasmonic devices. 1 Author to whom any correspondence should be addressed. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. New Journal of Physics 15 (2013) 073024 1367-2630/13/073024+17$33.00 © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft