Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-28T14:29:29.434Z Has data issue: false hasContentIssue false

The Effect of Surface Roughness on the Extinction Spectra and Electromagnetic Fields around Gold Nanoparticles

Published online by Cambridge University Press:  01 February 2011

Shuzhou Li
Affiliation:
[email protected], Northwestern University, Department of Chemistry, 2145 Sheridan Rd, Evanston, IL, 60208, United States
George C. Schatz
Affiliation:
[email protected], Northwestern University, Department of Chemistry, 2145 Sheridan Rd,, Evanston, IL, 60208, United States
Get access

Abstract

Electromagnetic enhancement arising from plasmon resonance excitation plays a major role in surface-enhanced Raman spectroscopy (SERS), and as a result nanoparticle morphology can significantly affect SERS intensities. In this paper we have calculated these enhancements as well as extinction spectra using the discrete dipole approximation for a system consisting of a dimer of gold disks that is made using on-wire lithography. Including surface roughness in the calculations leads to SERS enhancements for the disks whose dependence on disk spacing and thickness is in agreement with experimental measurements, with a maximum enhancement when the thickness of the disk and the disk-disk gap are 100 nm and 32 nm, respectively. These results are in better agreement with experiments than earlier estimates based on flat surfaces.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Moskovits, M., in Surface-Enhanced Raman Scattering: Physics and Applications (Topics in Applied Physics, Vol. 103) (Springer, Berlin, 2006), pp. 1; K. A. Willets and R. P. Van Duyne, Ann. Rev. Phys. Chem. 58, 267 (2007).Google Scholar
2. Schatz, G. C., Acct. Chem. Res. 17, 370 (1984).Google Scholar
3. Schatz, G. C., Y. M., , and Duyne, R. P. Van, in Surface-Enhanced Raman Scattering: Physics and Applications (2006), Vol. 103, pp. 19.Google Scholar
4. Kerker, M., Wang, D. S., and Chew, H., Appl. Opt. 19, 4159 (1980).Google Scholar
5. Bohren, C. F. and Huffman, D. R., Absorption and Scattering of Light by Small Particles. (Wiley-VCH, 2004).Google Scholar
6. Qin, L. D., Zou, S. L., Xue, C., Atkinson, A., Schatz, G. C., and Mirkin, C. A., Proc. Nat. Acad. Sci. 103, 13300 (2006).Google Scholar
7. Kneipp, K., Kneipp, H., and Kneipp, J., Acct. Chem. Res. 39, 443 (2006).Google Scholar
8. Qin, L. D., Park, S., Huang, L., and Mirkin, C. A., Science 309, 113 (2005).Google Scholar
9. Hagness, S. and Taflove, A., Computational Electrodynamics: The Finite-Difference Time-Domian Methods. (Boston, 2005); J. J. Goodman, B. T. Draine, and P. J. Flatau, Opt. Lett. 16, 1198 (1991).Google Scholar
10. Barabasi, A. L. and Stanley, H. E., Fractal concepts in surface growth. (Cambridge University Press, 1995).Google Scholar
11. Li, S. and Schatz, G. C., (to be published).Google Scholar
12. Kelly, K. L., Coronado, E., Zhao, L. L., and Schatz, G. C., J. Phys. Chem. B 107, 668 (2003); J. J. Goodman, B. T. Draine, and P. J. Flatau, Opt. Lett. 16, 1198 (1991).Google Scholar
13. Draine, B. T., User Guide to the Discrete Dipole Approximation Code DDSCAT6.1. (2004).Google Scholar
14. Johnson, P. B. and Christy, R. W., Phys. Rev. 12, 4370 (1972).Google Scholar
15. Hao, E. and Schatz, G. C., J. Chem. Phys. 120, 357 (2004).Google Scholar