Optofluidic system based on electrowetting technology for dynamically tunable spectrum absorber

An optofluidic system that uses the electrowetting technology to dynamically control the local surface plasmon resonance of the silver nanoparticle is invented. The silver nanoparticle is initially suspended at the interface of the polar liquid and the non-polar liquid. As the interface morphology changes with the applied voltage, the media distribution surrounding particle is changed accordingly, thus realizing the resonance absorption peak's modulation. The investigation result shows that a wide range of the spectral colors from red to blue can be selectively absorbed just by a single device. Specifically, when the radius of the particle is 50 nm, the wavelength of the absorption peak can be dynamically modulated from 460 nm to 607 nm. This proposed method can be used to design and prepare rapidly adjustable optical elements.