title: Electrowetting on liquid-infused film (EWOLF): complete reversibility and controlled droplet oscillation suppression for fast optical imaging.
abstract: Electrowetting on dielectric (EWOD) has emerged as a powerful tool to electrically manipulate tiny individual droplets in a controlled manner. Despite tremendous progress over the past two decades, current EWOD operating in ambient conditions has limited functionalities posing challenges for its applications, including electronic display, energy generation, and microfluidic systems. Here, we demonstrate a new paradigm of electrowetting on liquid-infused film (EWOLF) that allows for complete reversibility and tunable transient response simultaneously. We determine that these functionalities in EWOLF are attributed to its novel configuration, which allows for the formation of viscous liquid-liquid interfaces as well as additional wetting ridges, thereby suppressing the contact line pinning and severe droplet oscillation encountered in the conventional EWOD. Finally, by harnessing these functionalities demonstrated in EWOLF, we also explore its application as liquid lens for fast optical focusing.
authors.affiliation: Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: Chonglei
authors.initials: C
authors.lastname: Hao
authors.affiliation: Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: Yahua
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Civil and Architectural Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: Yuncheng
authors.initials: Y
authors.lastname: He
authors.affiliation: Department of Civil and Architectural Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: Qiusheng
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
authors.forename: K Y
authors.initials: KY
authors.lastname: Li
authors.affiliation: 1] Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China [2] Shezhen Research Institute of City University of Hong Kong, Shenzhen 518057, China.
authors.forename: Zuankai
authors.initials: Z
authors.lastname: Wang