Abstract

We present analysis of a whispering gallery mode resonator with a metallic nanorod bound to its surface. We show that the excitation of a localized surface plasmon resonance in the nanorod can reduce the optical mode volume of the resonator by as much as 3 × 10⁴ via a local enhancement of the electric field, and improve its detection sensitivity as a biological sensor. Optical frequency shifts as large as 15 MHz are predicted for typical proteins, and the minimum detectable molecular polarizability is calculated to be about 10 ų.

© 2011 AOS