Dynamic Modulation Of Surface Plasmon Resonance Based On Electrochromic Polymer

Surface Plasmon(SP)is a kind of near-field electromagnetic wave formed by the interaction of free electrons and photons at the metal-dielectric interface and propagates along the interface.It makes conventional photonics devices not limited by the diffraction of light.Surface Plasmon is a key nanotechnology to bridge between photonics and electronics on the nanoscales,which plays an important role in microdisplay,data storage,photonic chips,sensing technology,and nanofabrication.The research on active plasmonic devices whose plasmonic resonance properties can be controlled in real time has been a hot field in recent years.The active plasmonic devices based on electrochromic modulation show great potential on dynamic displays.The main research contents are the fast and reversible modulation of surface plasmon resonance by covering large-area nanostructures with electrochromic polymers.At present,metallic nanostructures are fabricated by top-down lithography technology,such as Focused Ion Beam(FIB)、Electron Beam Lithography(EBL),which are too time-consuming,costly,and complicated to obtain large-area metallic nanostructures.Here,a method obtaining large-area metallic nanostructures was proposed.The low-cost,large-area gold nanodisk array was fabricated with an assist of Anodic Aluminum Oxide template(AAO template).Control of surface plasmon resonance in real time was realized by PEDOT-coated gold nanodisk array.Experimental and numerical results demonstrated that fast and reversible electrochromic modulation of PCGN was realized with the change of driven voltages.The wavelength control of the localized surface plasmon resonance of the PCGN originated from the electrically driven refractive index change of the PEDOT film.With further explorations,this technique will be promising for high-yield manufactures of devices applied in dynamic reflective displays.For transmissive nanostructure,the gold nanohole array was obtained with an assist of polystyrene sphere,ICP oxygen etching,and physical vapor deposition,and explored the optic transmission in the different diameter and depth of nanohole.In order to control the extraordinary optical transmission(EOT)of gold nanohole array in real time,we reported a new electrochromic polymer,poly(EDOT-Pro DOT-EDOT),which can switch reversibly between magenta and transparent blue in the different redox state.Experiments results showed that the polymer owns good electrochemical activity,high optical contrast and fast response time.Gold nanohole array was covered by poly(EDOT-Pro DOT-EDOT)film with a method of electrochemical polymerization.The intensity of the SPR-enhanced optical transmission peak was actively tuned with the change of driven voltages.This research shows great potential in the field of optical switches and dynamic transmissive display in the future,which is promising for the high yield manufacturing of related devices.