Indexed by:Journal Article

Date of Publication:2012-10-01

Journal:CHINESE PHYSICS B

Included Journals:Scopus、ISTIC、EI、SCIE

Volume:21

Issue:10

ISSN:1674-1056

Key Words:surface plasmon polariton; nanolithography; finite difference time domain method

Abstract:The bowtie aperture surrounded by concentric gratings (the bull's eye structure) integrated on the near-field scanning optical microscopy (NSOM) probe (aluminum coated fiber tip) for nanolithography has been investigated using the finite-difference time domain (FDTD) method. By modifying the parameters of the bowtie aperture and the concentric gratings, a maximal field enhancement factor of 391.69 has been achieved, which is 18 times larger than that obtained from the single bowtie aperture. Additionally, the light spot depends on the gap size of the bowtie aperture and can be confined to sub-wavelength. The superiority of the combination of the bowtie aperture and the bull's eye structure is confirmed, and the mechanism for the electric field enhancement in this derived structure is analyzed.