title: Hemicylindrical and toroidal liquid microlens formed by pyro-electro-wetting.
abstract: We found that by opportune functionalization of a polar dielectric substrate, a self-arrangement of hemicylindrical or toroidal-shaped liquid droplets can be obtained. The process takes place when a thermal stimulus is provided to a poled substrate whose surface is covered by an oily substance layer. Liquid droplet self-arrangement is due to the pyroelectric effect, and interferometric characterization of the droplets is also reported. We investigated this open microfluidic system for exploring the possibility to obtain liquid cylindrical microlens with variable focal length. Liquid microtoroidal structures arrays are also realized. They could find application as resonant liquid microcavities for whispering gallery modes.
authors.affiliation: Istituto Nazionale di Ottica Applicata, CNR, Pozzuoli, Italy. lisa.miccio@inoa.it
authors.forename: Lisa
authors.initials: L
authors.lastname: Miccio
authors.forename: Melania
authors.initials: M
authors.lastname: Paturzo
authors.forename: Simonetta
authors.initials: S
authors.lastname: Grilli
authors.forename: Veronica
authors.initials: V
authors.lastname: Vespini
authors.forename: Pietro
authors.initials: P
authors.lastname: Ferraro