Figure 1.

False-colored SEM image of a plasmonic ring resonator and the corresponding transmittance over wavelength. (a) Top view and (b) cross section of the resonator. Photonic modes propagating in the buried silicon waveguide resonator couple partially to the SPPs in the metal-insulator-metal-ring when the resonance condition is fulfilled. While out of resonance operation results in a low loss light transmission. (c) Passive measurements of two identical ring resonators that only differ in radii (blue - 1030 nm; red - 1080 nm). Due to the resonant approach, insertion losses of 2.5 dB are measured with extinction ratios (ER) above 10 dB.