Numerical Modeling of Plasmonic Nanoantennas with Realistic 3D Roughness and Distortion

Sensors

Alexander V. Kildishev¹  Joshua D. Borneman²  Kuo-Ping Chen² 

[1] Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA;

关键词: optical sensing;    plasmonic nanoantenna;    plasmonic metamaterials;    surface roughness;    moving mesh;    finite element method;   

DOI  :  10.3390/s110707178

来源: mdpi

【 摘 要 】

Nanostructured plasmonic metamaterials, including optical nanoantenna arrays, are important for advanced optical sensing and imaging applications including surface-enhanced fluorescence, chemiluminescence, and Raman scattering. Although designs typically use ideally smooth geometries, realistic nanoantennas have nonzero roughness, which typically results in a modified enhancement factor that should be involved in their design. Herein we aim to treat roughness by introducing a realistic roughened geometry into the finite element (FE) model. Even if the roughness does not result in significant loss, it does result in a spectral shift and inhomogeneous broadening of the resonance, which could be critical when fitting the FE simulations of plasmonic nanoantennas to experiments. Moreover, the proposed approach could be applied to any model, whether mechanical, acoustic, electromagnetic, thermal, etc, in order to simulate a given roughness-generated physical phenomenon.

【 授权许可】

CC BY   
© 2011 by the authors; licensee MDPI, Basel, Switzerland.