Sensing with Surface Plasmons
presented by David Kerrigan C'20
Wednesday, March 6, 7:30 - 8:30pm, Woods Labs 216
Surface plasmon resonance (SPR) is the optical phenomenon where an evanescent wave is produced by the interaction of a light wave with the collective oscillations of surface charges under very specific conditions. It requires a dielectric medium and a metallic medium, usually gold, with free elections, and an incident light source, such as a helium-neon laser, to excite the surface-plasmon wave. Because it takes such specific conditions to produce, SPR is very sensitive to any changes in the optical configuration or the medium in contact with the gold layer surface. This high sensitivity provides good conditions for a sensor device. The sensing element is the gold layer, which can detect minute changes in the index of refraction of the adjacent medium. Today this technique is used extensively for biosensing due to its high sensitivity.
In my research, I am exploring a custom-built SPR setup to sense different indices of refraction of fluids in contact with a gold film.
David Kerrigan, C’20, is a junior physics major at the University of the South from Dallas, TX. He is a retired Sewanee lacrosse player and a member of the Sigma Nu fraternity. He plans to attend engineering school after graduation.