Near-Field Hot Spots in Gold Nanoplasmonic Templates and Their Use for Surface Enhanced Raman Scattering Sensing Application. (14th April 2014)

• Record Type: Journal Article
• Authors: Mandal, Prasanta
• Other Names: Chandra R. Academic Editor.; Shivpuri R. K. Academic Editor.
• Is Part Of: Conference papers in science. Volume 2014(2014)
• Publication Date: 2014-04-14
• Subjects: Science -- Periodicals; Science; Periodicals; 600
• DOI: 10.1155/2014/396826
• Languages: English
• ISSNs: 2356-6108

Abstract

Abstract : Finite difference time domain (FDTD) method is adapted to investigate near-field enhancement effects on plasmonic structures (patterned in gold film) such as concentric rings with small separation, square, and rectangle. The near-fields effect on surface enhanced Raman scattering (SERS) is typically studied on square and rectangular structures. These metal structures are fabricated by laser interference lithography. Raman active molecules (Rhodamine 6G in PMMA (polymethyl methacrylate)) are spread onto patterned structure by spin coating, and Renishaw inVia Raman spectrometer was used to study SERS. Typical SERS enhancement of the order of 10 5 is seen for square and rectangular structures. It is observed that the corner points and edges of square and rectangular structures are most sensitive to concentrate near fields. In the case of concentric rings, huge near fields are seen to exist at the gap between the metal rings. Concentric rings are proposed to be very effective structure for SERS sensing applications such as molecular identification and biological mapping.