Suchergebnisse

Plasmonic metasurfaces based on ensembles of distributed metallic nanostructures can absorb, scatter, and in other ways shape light at the nanoscale. Forming hybrid plasmonic metasurfaces by combination with other materials opens up for new research directions and novel applications. This perspective highlights some of the recent advancements in this vibrant research field. Particular emphasis is put on hybrid plasmonic metasurfaces comprising organic materials and on concepts related to switchable surfaces, light-to-heat conversion, and hybridized light-matter states based on strong coupling. ; Funding agencies: Wenner-Gren Foundations; Swedish Research CouncilSwedish Research Council; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linko

Heat sensors form an important class of devices that are used across multiple fields and sectors. For applications such as electronic skin and health monitoring, it is particularly advantageous if the output electronic signals are not only high, stable, and reproducible, but also self-generated to minimize power consumption. Here, we present an ultrasensitive heat sensing concept that fulfills these criteria while also being compatible with scalable low-cost manufacturing on flexible substrates. The concept resembles a traditional thermocouple, but with separated electrodes bridged by a gel-like electrolyte and with orders of magnitudes higher signals (around 11mVK(-1)). The sensor pixels provide stable and reproducible signals upon heating, which, for example, could be used for heat mapping. Further modification to plasmonic nanohole metasurface electrodes made the sensors capable of also detecting light-induced heating. Finally, we present devices on flexible substrates and show that they can be used to detect human touch. ; Funding Agencies|Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; Swedish Research CouncilSwedish Research CouncilEuropean Commission; Wenner-Gren Foundations; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]; Vinnova Digital Cellulose Competence Center (DCC)Vinnova [2016-05193]; Linkoping University; Treesearch.se.; Essity

State-of-the-art solar energy harvesting systems based on photovoltaic technology require constant illumination for optimal operation. However, weather conditions and solar illumination tend to fluctuate. Here, a device is presented that extracts electrical energy from such light fluctuations. The concept combines light-induced heating of gold nanodisks (acting as plasmonic optical nanoantennas), and an organic pyroelectric copolymer film (poly(vinylidenefluoride-co-trifluoroethylene)), that converts temperature changes into electrical signals. This hybrid device can repeatedly generate current pulses, not only upon the onset of illumination, but also when illumination is blocked. Detailed characterization highlights the key role of the polarization state of the copolymer, while the copolymer thickness has minor influence on performance. The results are fully consistent with plasmon-assisted pyroelectric effects, as corroborated by combined optical and thermal simulations that match the experimental results. Owing to the tunability of plasmonic resonances, the presented concept is compatible with harvesting near infrared light while concurrently maintaining visible transparency. ; Funding agencies: Wenner-Gren Foundations; Swedish Research Council [2015-05070]; Swedish Foundation for Strategic Research; AForsk Foundation; Royal Swedish Academy of Sciences; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Lin