Science Daily November 1, 2021 Lattice defects in crystals often come along with certain magnetic properties. To use them as promising systems for applications in quantum technologies an international team of researchers (Germany, Russia) has developed an efficient method to control their spin states using surface acoustic waves (SAW). They demonstrated a giant interaction between the strain field of SAW and the excited-state spin of silicon vacancies in silicon carbide, which is about two orders of magnitude stronger than in the ground state. The simultaneous spin driving in the ground and excited states with the same SAW leads to the […]
Top 10 Science and Technology Inventions for the Week of October 29, 2021
01. Controlling light with a material three atoms thick 02. Electrical control over designer quantum materials 03. Engineers develop flexible, self-healing material to protect steel from the elements 04. Nature’s strongest glue now works in both wet and salty environments 05. New chiral nanostructures to extend the material platform 06. On-water creation of conducting MOF nanosheets 07. Researchers develop broadband spintronic-metasurface terahertz emitters with tunable chirality 08. Researchers discover new way to generate light through use of pre-existing defects in semiconductor materials 09. Shape-shifting materials with infinite possibilities 10. Stronger than spider silk: Bagworm silk enables strong conducting fibers And […]
Controlling light with a material three atoms thick
Phys.org October 22, 2021 An international team of researchers (USA – Caltech, Japan) constructed a material from black phosphorous which has anisotropic optical properties. As the black phosphorous is a semiconductor, structures built from black phosphorous can control the polarization of light as an electric signal is applied to them. This makes it possible to make an array of these elements each of which can convert the polarization into a different reflected polarization state. A telecommunications device based on thin layers of black phosphorous could tune the polarization of each signal so that they don’t interfere with each other. This […]
Electrical control over designer quantum materials
Science Daily October 22, 2021 Recently engineered stacks of two-dimensional materials have emerged as a powerful platform for studying quantum correlations between electronic states. However, the strength of the interaction between the quantum states is typically fixed once a stack is fabricated. An international team of researchers (Switzerland, Japan) demonstrated that they can induce Feshbach resonance in their system allowing to tune the interaction strength between quantum entities by bringing them into resonance with a bound state. In their case the bounds states were between an exciton in one layer and a hole in the other layer. It turns out […]
Fighting viruses with interchangeable defense genes
Science Daily October 21, 2021 Although it is generally accepted that phages drive bacterial evolution, how these dynamics play out in the wild remains poorly understood. An international team of researchers (USA – MIT, Vienna, France) found that susceptibility to viral killing in marine Vibrio is mediated by large and highly diverse mobile genetic elements. These phage defense elements display exceedingly fast evolutionary turnover, resulting in differential phage susceptibility among clonal bacterial strains while phage receptors remain invariant. Protection is cumulative, and a single bacterial genome can harbor 6 to 12 defense elements, accounting for more than 90% of the […]
Engineers develop flexible, self-healing material to protect steel from the elements
Phys.org October 22, 2021 An international team of researchers (USA – Rice University, South Dakota School of Mines and Technology, SUNY Buffalo, George Washington University, Rensselaer Polytechnic Institute, Canada) has designed a lightweight sulfur–selenium (S–Se) alloy with high stiffness and ductility that can serve as an excellent corrosion-resistant coating with protection efficiency of ≈99.9% for steel in a wide range of diverse environments. S–Se coated mild steel showed a corrosion rate that is 6–7 orders of magnitude lower than bare metal in abiotic (simulated seawater and sodium sulfate solution) and biotic (sulfate-reducing bacterial medium) environments. The coating is strongly adhesive, […]
Nature’s strongest glue now works in both wet and salty environments
Phys.org October 27, 2021 An aquatic bacterium called Caulobacter crescentus produces an extremely powerful glue called “holdfast,” which adheres to its surrounding wet surfaces, such as pipes and fresh water. To improve holdfast adhesion in high salinity environments researchers in Canada compared Caulobacter crescentus with a marine relative called Hirschia baltica. They found both had the same genes to synthesize holdfast indicating they used the same type of glue. Hirschia baltica holdfast also appeared to perform very well in a saline environment, which is its natural environment. By manipulating the level of expression of a particular gene whose function is […]
New chiral nanostructures to extend the material platform
Phys.org October 22, 2021 The majority of previously developed chiral nanomaterials reveal the optical activity in a relatively shorter wavelength range (ultraviolet–visible, UV–vis), not in short-wave infrared (SWIR). An international team of researchers (South Korea, USA – University of Michigan) has demonstrated a versatile method to synthesize chiral copper sulfides using cysteine, as the stabilizer, and transferring the chirality from molecular- to the microscale through self-assembly. The assembled structures showed broad chiroptical activity in the UV–vis-NIR-SWIR region (200–2500 nm). They could tune the chiroptical activity by simply changing the reaction conditions. This approach can be extended to materials platforms for […]
On-water creation of conducting MOF nanosheets
Science Daily October 28, 2021 Researchers in Japan have created functional materials with advanced three-dimensional nanostructures that conduct electricity based on the idea that unique reactions occur at interfaces of water and oil. As they spread a solution containing organic linkers on aqueous solution of metal ions the substances begin assembling their components in a hexagonal arrangement forming nanosheets where the liquid and air meet. They used two barriers to compress the nanosheets into more dense and continuous state. The process produced thin nanosheets with highly organized crystalline structures, tightly ordered crystals also indicated the electrical properties of the material. […]
Physics experiment in Earth’s atmosphere could help improve GPS performance
Phys.org October 27, 2021 Plasma in the ionosphere plays a significant role in reflecting and modifying radio waves used for communication and radio navigation systems such as GPS, but the accuracy of these can be affected by ‘space weather’ events such as solar storms. The space weather events dynamically increase the total number of ionospheric electrons; GPS systems cannot correctly model this dynamic enhancement and errors occur in position calculations. An international team of researchers (UK, Norway, Portugal) conducted a controlled radar wave experiment by injecting radio waves into the ionosphere, at slightly different frequencies. By annlyzing the returned signals […]