Nanoholes arrays as effective SERS substrates with multiple wavelength SERS response and large electromagnetic SERS enhancement factors

Nitin Gupta; Rajib R. Ghosh; Anuj Dhawan

doi:10.1117/12.2510828

7 March 2019 Nanoholes arrays as effective SERS substrates with multiple wavelength SERS response and large electromagnetic SERS enhancement factors

Nitin Gupta, Rajib R. Ghosh, Anuj Dhawan

Author Affiliations +

Proceedings Volume 10894, Plasmonics in Biology and Medicine XVI; 1089418 (2019) https://doi.org/10.1117/12.2510828
Event: SPIE BiOS, 2019, San Francisco, California, United States

Abstract

Bridged-bowtie nanohole arrays and cross bridged-bowtie nanohole arrays in a gold film are presented as surfaceenhanced Raman scattering (SERS) substrates. We employed the numerical FDTD method to calculate the maximum electromagnetic SERS enhancement factor (EF) as a function of wavelength. It is found that the proposed nanohole arrays do not only display an extremely large enhancement factor but also have the hotspot spread over a larger area compared to the various other nanopillar structures. The calculation of electromagnetic SERS enhancement factor reveals that the cross bridged-bowtie nanohole arrays exhibit the maximum electromagnetic SERS EF of ~ 10⁹ spreading over an area of 100 nm². In addition, the electromagnetic SERS EF of ~ 10⁸ is spread over 500 nm² area which is higher than hotspot area in case of nanopillar structures. The resonance wavelength of the nanohole array can be tuned by varying the size of the nanoholes. These nanohole arrays can be employed both in transmission as well as in reflection mode as effective SERS substrates. In addition, bridged-bowtie and cross bridged-bowtie nanohole arrays show the significantly high electromagnetic SERS EF at more than one wavelength and therefore are useful for application involving multiple wavelength SERS response. Furthermore, the cross bridged-bowtie nanohole array exhibit the spatial tunability of hotspot by rotating the direction of polarization of incident field.

Citation Download Citation

Nitin Gupta, Rajib R. Ghosh, and Anuj Dhawan "Nanoholes arrays as effective SERS substrates with multiple wavelength SERS response and large electromagnetic SERS enhancement factors", Proc. SPIE 10894, Plasmonics in Biology and Medicine XVI, 1089418 (7 March 2019); https://doi.org/10.1117/12.2510828

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available