Dielectrophoretically controlled Fresnel zone plate. Issue 4 (19th December 2014)

• Record Type: Journal Article
• Authors: Chrimes, A. F.; Khodasevych, I.; Mitchell, A.; Rosengarten, G.; Kalantar-zadeh, K.
• Is Part Of: Lab on a chip. Volume 15:Issue 4(2015)
• Page Start: 1092
• Page End: 1100
• Publication Date: 2014-12-19
• Subjects: Miniature electronic equipment -- Periodicals; Combinatorial chemistry -- Periodicals; Biotechnology -- Periodicals; 543.0813
• DOI: 10.1039/c4lc01213e
• Languages: English
• ISSNs: 1473-0197

Abstract

Abstract : We present a novel switchable Fresnel zone plate, created using nanoparticle suspensions which are controlled by dielectrophoresis. Abstract : Switchability is a highly sought after feature for planar optical systems. Suspensions of nanomaterials can be used for generating controllable changes in such systems. We report a planar diffractive microfluidic lens which integrates controlled dielectrophoresis (DEP) for trapping suspended nanomaterials. Silicon and tungsten oxide nanoparticle suspensions are used. These nanomaterials are trapped in such a way as to form alternating opaque and transparent rings using the DEP forces on demand. These rings form a planar diffractive Fresnel zone plate to focus the incident light. The Fresnel zone plate is tuned for the visible light region and the lens can be turned on (DEP applied) or off (DEP removed) in a controlled manner. This proof of concept demonstration can be further expanded for a variety of switchable optical devices and can be integrated with lab-on-a-chip and optofluidic devices.