Research Letters in Physics
Volume 2008 (2008), Article ID 148505, 5 pages
doi:10.1155/2008/148505
Research Letter

Nanopinholes-Based Optical Superlens

Yongqi Fu,1 Chunlei Du,1 Wei Zhou,2 and Lennie Enk Ng Lim2

1State Key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
2Precision Engineering and Nanotechnology Centre, School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore

Received 10 October 2007; Accepted 3 January 2008

Academic Editor: Nathan Ida

Copyright © 2008 Yongqi Fu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A type of nanopinhole-based plasmonic structure is presented. It can realize superfocusing within micron-scale propagation distance with spatial resolution beyond diffraction limit. Cut-off wavelength effect is highlighted for understanding how periodicity distribution of the nanopinholes influences transmission and focusing through the structure. Redshift peak transmission occurs while the periodicity increases. In addition, focusing property of the plasmonic structures is analyzed for the monochromatic illumination with different incident wavelengths ranging from 400 nm to 750 nm. The easy fabrication and high focusing performance of the proposed structures may be used in data storage devices, bioimaging, and nanolithography.