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Metamaterials concept has been under extensive development over the past two decades and has been proven to be beneficial for a wide range of practical applications in both microwave and optical spectral ranges. In particular, it is commonly used for tailoring light-matter interactions on nanoscale. While many different approaches towards metamaterials fabrication exist, most of them are limited to “top-down” concept, including but not limited to lithographic methods, like photolithography, e-beam and nanoimprint lithography. On the other hand, the “bottom-up” chemical self-assembly techniques offer several distinctive advantages like throughput and cost-effectiveness, allowing large-scale production of composites. Here a novel metamaterial platform, based on mesoporous vaterite particles (further referred to as cargoes) is proposed and demonstrated. Controllable doping of micron and sub-micron scale dielectric hosts with metal nanoparticles enables tuning effective plasma frequency of new composites and, as the result, allows tailoring properties of collective localized plasmon resonances that they support. Furthermore, newly developed fabrication protocols enable introducing active materials (e.g. dyes and colloidal quantum dots) within vaterite cargoes and tailor their emission properties. Introduction of high concentration of active materials into compound particles allows compensating material losses in the medium with gain. Moreover, by coating the surface of the particles with passivating agents, it is possible to achieve long-term stability of such compound cargos in different types of solvents. Both unrestricted three-dimensional motion (compared to two-dimensional trapping of metallic particles) and rotation by circularly polarized trapping beams were demonstrated. Theoretical, numerical and experimental studies of those novel composites with beforehand mentioned properties will be presented. The vaterite-based metamaterial platform paves a way to new fundamental investigations and enables to introduce concepts of ultra-bright controllably floating imaging agents for relevant bio-medical applications.
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