LoboVault Home

Improvement of the electromagnetic enhancement in surface enhanced Raman spectroscopy

LoboVault

Please use this identifier to cite or link to this item: http://hdl.handle.net/1928/3283

Improvement of the electromagnetic enhancement in surface enhanced Raman spectroscopy

Show full item record

Title: Improvement of the electromagnetic enhancement in surface enhanced Raman spectroscopy
Author: Zhang, Chao
Advisor(s): Christodoulou, Christos
Committee Member(s): Schamiloglu, Edl
El-Kady, Ihab
Department: University of New Mexico. Dept. of Electrical and Computer Engineering
Subject: SERS
LC Subject(s): Raman spectroscopy
Degree Level: Masters
Abstract: In this thesis, several ways to improve the electromagnetic (EM) enhancement in Surface Enhanced Raman Spectroscopy (SERS) are explored. Some factors influencing the EM enhancement, including material, polarization, size, shape, and arrangement are analyzed and optimized. With 33 years old history, SERS is a powerful technique, applied widely in chemical and biological sensing. However, the enhancement is no more than $10^6$ - $10^8$ in conventional methods of SERS, which is not high enough in some applications such as single molecule detection. In the last ten years, the single molecule detections by SERS are obtained only by some special enhancement: additional chemical enhancement or fractal silver colloids. The objective of this work is to design a synthesized scheme which may improve the EM enhancement directly up to $10^{14}$, at the level of single molecule detection, in a systematic array with high reproducibility. So far there is still no satisfying theory that can describe and explain SERS perfectly. To clarify the mechanism of enhancement, EM and non-EM enhancements are split. Analyzing several kinds of factors, this thesis introduces the two-body interaction principle and describes the space charge distribution model, to help understand how to optimize these factors. Numerical results using the FDTD method have verified the conclusions and are also used to design an optimized particle array. Moreover, the additional enhancements can be achieved, if the particle array is put inside an optical cavity with proper resonant frequency. By storing the energy inside a closed region, the EM enhancement gets improved further.
Graduation Date: July 2007
URI: http://hdl.handle.net/1928/3283


Files in this item

Files Size Format View
2.1.pdf 5.051Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record

UNM Libraries

Search LoboVault


Browse

My Account