Abstract
Surface plasmon resonance (SPR) is currently used as an optical immunassay technique for the detection of various analytes. The uniformity of the metal film and the wavefront structure of the incident beam have an effect on the sensitivity of the SPR technique, yet most analysis methods are not capable of considering inhomogeneous layers or nonplanar excitation beams. We have applied a new numerical electromagnetic method, called finite-difference time- domain (FDTD), to this problem. To correctly model the time domain behavior of the electron oscillations, the dynamic force equation is applied to a Drude free electron model of the metal. We have analyzed a particular SPR configuration consisting of an incident beam of finite size (approximating a focused beam) onto a smooth silver film, and have obtained Poynting vector plots and reflectivity data for this configuration. The angle and magnitude of minimum reflectivity are similar for the FDTD results compared to theoretical predictions, but the angular width of the reflectivity minimum is broadened. We have also analyzed a model of a rough metal film, and find that the local electric fields are enhanced near the metal edges.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
