Large shift of resonance wavelengths of silver nanoslit arrays using electrowetting-on-dielectric cells

A simple design for shifting the resonance wavelength of silver nanoslits using an electrowetting-on-dielectric (EWOD) cell is proposed. The EWOD cell comprises a polycarbonate (PC) substrate with Teflon-coated silver nanoslits and a glass substrate with Teflon-coated electrodes. A glycerol droplet is placed between the two substrates, and out of the path of a probe beam at zero electric field. Application of an electric field smaller than 0.3 V/mu m on the electrodes moves the glycerol droplet into the path of the probe beam, shifting the resonance wavelength of the silver nanoslits by 135 nm. A change (0.33) in the refractive index of the effective medium that is adjacent to the silver nanoslits causes a large shift in the resonance wavelength. The spectral shift of the silver nanoslits is repeatable by the electric field. This simple design is a great achievement for high-performance electro-optical devices with large wavelength shift ranges such as optical switches, variable optical attenuators, and sensor applications. (C) 2021 Optical Society of America

Automated summary

This study presents a simple design for shifting the resonance wavelength of silver nanoslits using an EWOD cell, demonstrating the ability to shift the resonance wavelength by moving a droplet with an electric field. The wavelength shift of 135 nm can be achieved by adjusting the electric field, making it suitable for high-performance electro-optical devices.