Jon-Paul Maria, Department of Materials Science and Engineering, The Pennsylvania State University, USA
Electroceramic Thin Films for IR Plasmonic Applications
Abstract: Transparent conductive oxides (TCOs) are an attractive materials platform for plasmonics and metamaterials in the near- and mid-infrared (MIR). This presentation will briefly review plasmonic oscillation modes, some interesting applications for plasmon polaritons, and the conductors and devices that have been recently explored. Among TCOs, the doped electroceramic cadmium oxide (CdO) exhibits exceptional electronic and plasmonic characteristics with tunable carrier concentration and high electron mobility, which enables low-loss plasmonic resonances. We have shown that through careful control of thin film growth and defect chemistry, doped CdO supports high quality plasmonic resonances across the entire MIR with tunable carrier concentrations spanning nearly than two orders of magnitude accompanied by maximum carrier mobilities over 500 cm^2/V·s.
We will show that by controlling electron concentration, mobility, thickness, and film-substrate geometry, we can grow doped CdO films to target multiple plasmonic modes, including surface plasmon polaritons (SPP), epsilon-near-zero (ENZ) modes, and Brewster/Berreman modes. Additionally, by growing stacked doped/intrinsic/doped CdO layers we are able to access additional SPP dispersion branches below the lightline resulting from coupling between the doped layers. Such control further allows us to grow multilayer CdO films with arbitrary layer thickness and doping: in a single stack, we achieve multiple (3+) absorption peaks associated with the ENZ modes of each individual layers. We will also show that these stacks also display multiple thermal emission peaks, also associated with the ENZ mode frequency of individual layers. As they require no lithography and contain no physical interfaces, these devices are, in effect, “bulk metamaterials.” This discovery enables a scalable method to engineer the optical properties of monolithic MIR metamaterials for MIR absorption and emission by design.
Yet-Ming Chiang, Kyocera professor, Materials Science and Engineering Department, Massachusetts Institute of Technology, USA
Ceramics are Enabling the Next Generation of Energy Storage Technologies
Abstract: The advent of near-zero cost renewable electricity coupled with other societal trends is driving the development of new energy storage technologies for transportation and electric power. Even before the inception of the lithium-ion battery three decades ago, ceramic materials played a central role in battery technologies as either ion storage host or electrolyte. This remains true across multiple current trends in electrochemical storage, which can be broadly distinguished by a focus on very high energy density storage for portable devices and/or transportation (including air vehicles), or very low cost storage to enable reliable, dispatchable power from intermittent renewable electricity generation. The performance and techno-economic drivers for energy storage in these sectors will be discussed. Several examples will be given that highlight the important role that compositional design, physical properties, and processing of ceramic components continue to play in enabling new battery technologies.