Eurekalert June 1, 2018 An international team of researchers (Switzerland, Spain, USA – Princeton University, Germany, France) has predicted a new class of topological insulators, called “higher-order topological insulators”, that have conducting properties on the edges of crystals rather than on their surface. The conducting edges are extraordinarily robust. If an imperfection gets in the way of the current, it simply flows around the impurity, if the crystal breaks, the new edges automatically conduct current and in theory electricity can be conducted without any dissipation. They have proposed tin telluride as the first compound to show these novel properties. The […]
Category Archives: Advanced materials
Plastic crystals hold key to record-breaking energy transport
Nanowerk May 29, 2018 Researchers in the UK developed a new way to make highly ordered crystalline semiconducting structures using polymers. The distance that the photo-exited states travelled reached distances of 200 nanometres – 20 times further than was previously possible. 200 nanometres is especially significant because it is greater than the thickness of material needed to completely absorb ambient light, making these polymers more suitable as “light harvesters” for solar cells and photodetectors… read more. TECHNICAL ARTICLE
Researchers develop electronic skins that wirelessly activate fully soft robots
Phys.org June 01, 2018 Skin-like electronic system proposed by researchers in South Korea consists of two-part electronic skins (e-skins) that are designed to perform wireless inter-skin communication for untethered, reversible assembly of driving capability. The physical design of each e-skin features minimized inherent hardness in terms of thickness, weight, and fragmented circuit configuration. The e-skin pair can be softly integrated into separate soft body frames (robot and human), wirelessly interact with each other, and then activate and control the robot. The design is highly compact and shows that the embedded e-skin can equally share the fine soft motions of the […]
An elastic fiber filled with electrodes set to revolutionize smart clothes
Science Daily May 25, 2018 Using thermal drawing researchers in Switzerland created hundreds‐of‐meters long multimaterial optical and electronic fibers and devices that can sustain up to 500% elastic deformation before recovering their initial shape. The fibers can detect even the slightest pressure and strain that makes them perfect for applications in smart clothing and prostheses, and for creating artificial nerves for robots… read more. TECHNICAL ARTICLE
Scientists discover new magnetic element
Phys.org May 24, s018 A team of researchers in the US (University of Minnesota, University of Wisconsin, industry) has demonstrated single element ferromagnetism in ruthenium. They observed a saturation magnetization of 148 and 160 emu cm−3 at room temperature and 10 K, respectively. Increasing thickness results in strain relaxation, and thus diluting the magnetization. Anomalous Hall measurements are used to confirm its ferromagnetic behavior. The discovery could be used to improve sensors, devices in the computer memory and logic industry, or other devices using magnetic materials… read more. Open Access TECHNICAL ARTICLE
Dielectric metamaterial is dynamically tuned by light
Nanowerk May 1, 2018 A team of researchers in the US (Duke University, UC San Diego) has developed a technology where each grid location of a metamaterial contains a photodoped silicon cylinder making it conductive. The size of the cylinders dictates what frequencies of light they can interact with, while the angle of the photodoping affects how they manipulate the electromagnetic waves. For demonstration they sized the cylinder to interact with terahertz waves. According to the researchers controlling terahertz waves could improve broadband communications between satellites, and lead to security technology. The approach could also be adapted to other bands […]
A surprising new superconductor
Science Daily May 1, 2018 A team of researchers in the US (NIST, University of Colorado, University of Nevada Las Vegas, Argonne National Laboratory, Syracuse University) has shown that electroplated rhenium (Re) films in multilayers with metals such as Cu, Au, and Pd have an enhanced superconducting critical temperature relative to previous methods of preparing Re. The dc resistance and magnetic susceptibility indicate a critical temperature of approximately 6 K. It meets ideal characteristics desired for use in circuit boards for ultrafast, next-generation computing applications: superconducting at higher, easier-to-achieve critical temperatures, easy to work with mechanically, non-toxic, and melts at high […]
New carbon-dioxide-adsorbing crystals could form the basis of future biomedical materials that rely on the shape-memory effect
Science Daily April 27, 2018 The shape-memory effect in crystalline porous materials is poorly understood. An international team of researchers (Ireland, Japan, University of Southern Florida) reports the porous coordination network that exhibits a sorbate-induced shape-memory effect in which multiple sorbates, N2, CO2 and CO promote the effect. It exhibits three distinct phases: the as-synthesized α phase; a denser-activated β phase; and a shape-memory γ phase. Analysis of the structural information of the three phases helped them to understand structure-function relationships and propose crystal engineering principles for the design of more examples of shape-memory porous materials… read more. Open Access […]
Scientists create nanomaterials that reconfigure in response to biochemical signals
Phys.org April 30, 2018 The ability to self-assemble, reconfigure and disassemble in response to chemical signals is a common trait in biological materials, but not in manmade ones. A team of researchers in the US (City University of New York, UC Irvine) started with the base molecule naphthalenediimide (NDI), which is an organic semiconductor, and selectively modified it on both sides by exposing to biochemical signals in the form of simple amino acids. This process allowed the formation and degradation of nanomaterials with wire-like features capable of conducting electrical signals. By using different amino acids, researchers were able to direct […]
Scientists find a new way to make novel materials by ‘un-squeezing’
Nanowerk May 1, 2018 A team of researchers in the US (NERL, University of Colorado, University of Connecticut, SLAC National Accelerator Laboratory) mixed high-density forms of manganese selenide and manganese telluride that have different crystal structures by sputtering in which fine sprays of atoms were freed from the surfaces of both starting materials and deposited as a thin film on a hot surface, where the new alloy crystallized and grew. The new alloy had the crystal structure of yet another mineral, wurtzite. Finding new routes to synthesize materials that nature cannot make would catalyze progress towards next-generation technologies… read more. […]