Information display utilizing plasmonic color generation has recently emerged as an alternative paradigm to traditional printing and display technologies. However, many implementations so far have either presented static pixels with a single display state or rely on relatively slow switching mechanisms such as chemical transformations or liquid crystal transitions. Here, we demonstrate spatial, spectral, and temporal control of light using dynamic plasmonic pixels that function through the electric-field-induced alignment of plasmonic nanorods in organic suspensions. By tailoring the geometry and composition (Au and Au@Ag) of the nanorods, we illustrate light modulation across a significant portion of the visible and infrared spectrum (600–2400 nm). The fast (∼30 μs), reversible nanorod alignment is manifested as distinct color changes, characterized by shifts of observed chromaticity and luminance. Integration into larger device architectures is showcased by the fabrication of a seven-segment numerical indicator. The control of light on demand achieved in these dynamic plasmonic pixels establishes a favorable platform for engineering high-performance optical devices.

Many emerging applications in microscale engineering rely on the fabrication of 3D architectures in inorganic materials. Small-scale additive manufacturing (AM) aspires to provide flexible and facile access to these geometries. Yet, the synthesis of device-grade inorganic materials is still a key challenge toward the implementation of AM in microfabrication. Here, a comprehensive overview of the microstructural and mechanical properties of metals fabricated by most state-of-the-art AM methods that offer a spatial resolution ≤10 μm is presented. Standardized sets of samples are studied by cross-sectional electron microscopy, nanoindentation, and microcompression. It is shown that current microscale AM techniques synthesize metals with a wide range of microstructures and elastic and plastic properties, including materials of dense and crystalline microstructure with excellent mechanical properties that compare well to those of thin-film nanocrystalline materials. The large variation in materials' performance can be related to the individual microstructure, which in turn is coupled to the various physico-chemical principles exploited by the different printing methods. The study provides practical guidelines for users of small-scale additive methods and establishes a baseline for the future optimization of the properties of printed metallic objects-a significant step toward the potential establishment of AM techniques in microfabrication.

Direct calorimetric measurements of a solid state passive switchable radiator for spacecraft thermal control have been performed in a simulated space environment. Dynamic emissivity control is provided by the thermochromic phase change in a multilayer VO 2 thin film based resonant absorber. The measured radiated power difference between 300 K and 373 K was 480 W/m 2 corresponding to a 7× difference in radiative cooling power. We present theoretical and experimental radiator values for both normal and hemispherical as well the optical properties of VO 2 as determined via infrared spectroscopic ellipsometry.

The discovery of low-dimensional metallic systems such as high-mobility metal oxide field-effect transistors, the cuprate superconductors, and conducting oxide interfaces (e.g., LaAlO3/SrTiO3) has stimulated research into the nature of electronic transport in two-dimensional systems given that the seminal theory for transport in disordered metals predicts that the metallic state cannot exist in two dimensions (2D). In this report, we demonstrate the existence of a metal–insulator transition (MIT) in highly disordered RuO2 nanoskins with carrier concentrations that are one-to-six orders of magnitude higher and with mobilities that are one-to-six orders of magnitude lower than those reported previously for 2D oxides. The presence of an MIT and the accompanying atypical electronic characteristics place this form of the oxide in a highly diffusive, strong disorder regime and establishes the existence of a metallic state in 2D that is analogous to the three-dimensional case.

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Electronic paper, or e-Paper, for use in displays has seen rapid growth in the past decade because of its potential as an alternative to traditional transmissive displays. Offering several critical advantages over current display technologies, including high contrast in direct sunlight, wide viewing angles, and compatibility with flexible substrate processing, electrowetting displays (EWDs) have made it to the forefront of e-Paper research and development efforts. Here, we describe a new design for the fabrication of multi-color, bistable electrowetting displays. Using a laser-based process to pattern an in-plane electrode design, liquid can be manipulated out-of-plane. This process relies on electromechanical pressure forcing water in and out of channels, causing colored oil to be displaced. When voltage is removed, the oil remains in its current position, resulting in bistability. We have demonstrated multi-color, bistable pixels that maintain their state at for several days, which drastically reduces the power required to drive the display.