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Researchers from the George Washington University, the University of California, Los Angeles, and City College of New York, have revealed a new nanophotonic analog processor capable of solving partial differential equations. This nanophotonic processor can be integrated at chip-scale, processing arbitrary inputs at the speed of light.
In recent years, nanophotonics at infrared and terahertz frequencies has become important for highly sensitive, ultracompact and low-loss technologies for bio-molecular and chemical diagnosis, sensors, communications and other applications. Now, an international team led by scientists at the City University of New York, Huazhong University of Science and Technology, National University of Singapore, and National Center for Nanoscience and Technology in Beijing has reported that calcite – a bulk crystal commonly used in other technologies – can naturally support ghost polaritons, which are a new form of surface waves carrying light at the nanoscale that is strongly coupled with material oscillations and featuring highly collimated propagation properties.
Scientists at Rice University have sewn nanotube fibers into athletic wear to monitor the wearer’s heart rate and take a continual electrocardiogram (EKG) of the wearer. The fibers are just as conductive as metal wires, but washable, comfortable and far less likely to break when a body is in motion. On the whole, the enhanced shirt was better at gathering data than a standard chest-strap monitor taking live measurements during experiments.
Scientists at Carnegie Mellon University, the University of Pittsburgh, Drexel University, and the University of Pennsylvania have measured the photothermal properties of transition metal carbides/nitrides (MXenes), unique two-dimensional nanomaterials, at a single flake level. The scientists dispersed flakes on the surface of dorsal root ganglion, cells in the peripheral nervous system, and illuminated them with short pulses of light. By studying the interface between cells and materials, the scientists were able to accurately measure the amount of light required to create cellular change.
Scientists at the U.S. Department of Energy’s Argonne National Laboratory have discovered that nanoparticles of gold act unusually when close to the edge of graphene, a one-atom thick sheet of carbon. When the scientists shine light on the nanoparticles, the light triggers waves of electrons called plasmonic fields. When the nanoparticles sit on a flat sheet of graphene, the plasmonic field is symmetric. But when the nanoparticle is positioned close to a graphene edge, the plasmonic field concentrates much more strongly near the edge region. This discovery could have implications for the development of new sensors and quantum devices.
For the first time, engineers at Northwestern University have created a double layer of atomically flat borophene, a feat that defies the natural tendency of boron to form non-planar clusters beyond the single-atomic-layer limit. Although known for its promising electronic properties, borophene -- a single-atom-layer-thick sheet of boron -- is challenging to synthesize. Unlike its analog two-dimensional material graphene, which can be peeled away from innately layered graphite using something as simple as scotch tape, borophene cannot merely be peeled away from bulk boron. Instead, borophene must be grown directly onto a substrate.
Scientists at the U.S. Department of Energy's Ames Laboratory have discovered that an unwanted byproduct of their experiments is a high-quality substance sought after by scientists researching layered materials. The scientists’ focus is magnesium diboride. But they also produce hexagonal boron nitride, a highly sought-after and difficult-to-obtain insulating material for scientists researching graphene, the 2D layered semimetal that was first discovered in 2010.
Optoelectronics, a technology that gives off, detects, or controls light, is used everywhere in modern electronics and includes light-emitting diodes and solar cells. Within these devices, the movement of excitons (pairs of negative electrons and positive holes) determines how well the device performs. Until now, the distance that excitons could travel in conventional optoelectronic systems was around 30-70 nanometers, and there was no way to directly image how the excitons move. Now, a team of researchers from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the Swiss Federal Institute of Technology Lausanne has designed and made a nanocrystal system in which excitons can move a record distance of 200 nanometers, an order of magnitude larger than what was previously possible.
Scientists from the U.S. Department of Energy’s Brookhaven National Laboratory, the University of Pennsylvania, the University of New Hampshire, the Chinese University of Hong Kong, Stony Brook University, and Columbia University have detected electronic and optical interlayer resonances in two different configurations of bilayer graphene—the two-dimensional (2D), atom-thin form of carbon. They found that twisting one of the graphene layers by 30 degrees relative to the other, instead of stacking the layers directly on top of each other, shifts the resonance to a lower energy. From this result, they deduced that the distance between the two layers increased significantly in the twisted configuration, compared to the stacked one.
Researchers from the University of Texas at Austin, in collaboration with the U.S. Army Research Lab, are analyzing new materials for electrical insulation that can remove heat more effectively compared to today's insulation. They provide a critical review and perspectives of new nanocomposite materials from an engineering and reliability perspective.
