Improving near-field confinement of a bowtie aperture using surface plasmon polaritons

Pornsak Srisungsitthisunti, Birck Nanotechnology Center, Purdue University
Okan Ersoy, Purdue University
Xianfan Xu, Birck Nanotechnology Center, Purdue University

Date of this Version



Appl. Phys. Lett. 98, 223106 (2011)


Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 98, 223106 (2011) and may be found at The following article has been submitted to/accepted by Applied Physics Letters. Copyright (2011) Pornsak Srisungsitthisunti, Okan K. Ersoy and Xianfan Xu. This article is distributed under a Creative Commons Attribution 3.0 Unported License.


Bowtie aperture is known to produce subdiffraction-limited optical spot with high intensity. In this work, we investigate integrating a bowtie aperture with circular grooves to reduce the divergence of the near-field produced by the bowtie aperture. Numerical results indicate that surface waves reflected from circular grooves improve the field confinement of a bowtie aperture along the polarization axis. These circular grooves with period near half the wavelength of surface plasmon polaritons reduce the spot size by as much as 40% at distances between 20 and 100 nm from the surface and create a more symmetrical optical spot. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3595412]


Nanoscience and Nanotechnology