Metamaterials are artificially made materials, whose properties may not exist in nature. The goal of this thrust area is to synthesize artificial structures such as superlattices and nano-composites, which demonstrate desirable transport properties for energy and electronic device applications.
For example, achieving low thermal conductivity materials have enormous impact on both thermoelectrics and thermal management. Most naturally occurring materials do not possess low thermal conductivity besides other desirable properties such as high electrical conductivity, excellent mechanical stability etc. Metamaterials provide a novel route to explore the realization of contrasting properties by artificially tailoring the length scales in a system. Superlattices, (STEM images of superlattices of complex oxides are shown in the figure below) where two different materials are arranged periodically and show long range order, are good model systems to explore the limits of thermal transport. This understanding will open up the opportunity to engineer thermal and thermoelectric properties of materials by designing the structures from the bottom up.
Scanning Transmission Electron Microscopic images of Superlattices of [(CaTiO3)2/(SrTiO3)2] (left) and [(BaTiO3)/(SrTiO3)30] (right)
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