High-contrast and fast electrochromic switching enabled by plasmonics

• Published in: Nature communications 2016-01, Vol.7 (1), p.10479-10479, Article 10479
• Main Authors: Xu, Ting, Walter, Erich C., Agrawal, Amit, Bohn, Christopher, Velmurugan, Jeyavel, Zhu, Wenqi, Lezec, Henri J., Talin, A. Alec
• Format: Article
• Language: English
• Subjects: 142/126; 639/624/400/1021; 639/638/440; 639/766/119/544; 639/925; Humanities and Social Sciences; MATERIALS SCIENCE; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms10479

With vibrant colours and simple, room-temperature processing methods, electrochromic polymers have attracted attention as active materials for flexible, low-power-consuming devices. However, slow switching speeds in devices realized to date, as well as the complexity of having to combine several distinct polymers to achieve a full-colour gamut, have limited electrochromic materials to niche applications. Here we achieve fast, high-contrast electrochromic switching by significantly enhancing the interaction of light—propagating as deep-subwavelength-confined surface plasmon polaritons through arrays of metallic nanoslits, with an electrochromic polymer—present as an ultra-thin coating on the slit sidewalls. The switchable configuration retains the short temporal charge-diffusion characteristics of thin electrochromic films, while maintaining the high optical contrast associated with thicker electrochromic coatings. We further demonstrate that by controlling the pitch of the nanoslit arrays, it is possible to achieve a full-colour response with high contrast and fast switching speeds, while relying on just one electrochromic polymer. Slow switching speeds in device configurations have severely limited the applications of electrochromic materials. Here, Xu et al . use plasmonic nanoslit arrays and demonstrate fast, high-contrast, monochromatic and full-colour electrochromic switching using two different electrochromic polymers.