Science Daily September 14, 2020 An international team of researchers (Austria, Russia, the Netherlands) found that in langasite made of lanthanum, gallium, silicon and oxygen, doped with holmium atoms even small changes in the direction of the magnetic field can switch the electrical properties of the material to a completely different state even though it has a crystal structure that is so symmetrical that it should actually not allow any magnetoelectric effect for theoretical reasons. In the case of weak magnetic fields there is no coupling whatsoever with the electrical properties of the crystal. But if the strength of the […]
Physicists make electrical nanolasers even smaller
EurekAlert September 16, 2020 An international team of researchers (Russia, UK) has developed a new approach to create electrically driven nanolasers for integrated circuits. In their approach electrical pumping is based on a double heterostructure with a tunneling Schottky contact. Plasmon-polaritons (SPPs) replace photons. The pumping happens across the interface between the plasmonic metal and semiconductor, along which surface SPPs propagate. The pumping approach makes it possible to bring the electrically driven laser to the nanoscale, while retaining its ability to operate at room temperature and the radiation is effectively directed to a photonic or plasmonic waveguide, making the nanolaser […]
Physicists ‘trick’ photons into behaving like electrons using a ‘synthetic’ magnetic field
Nanowerk September 14, 2020 Researchers in the UK have shown that it is possible to create artificial magnetic fields for light by distorting honeycomb metasurfaces that are engineered to have structure on a scale much smaller than the wavelength of light. They embedded the metasurface in photonic cavity and showed that it is possible to tune the artificial magnetic field by changing only the width of the photonic cavity, thereby removing the need to modify the distortion in the metasurface. Using this mechanism it is possible to bend the trajectory of the polaritons using a tunable Lorentz-like force and also […]
Single atom-thin platinum makes a great chemical sensor
EurekAlert September 14, 2020 Researchers in Sweden prepared one atom thin, electrically continuous platinum layers by physical vapor deposition on the carbon zero layer (buffer layer) grown epitaxially on silicon carbide. With a thin Pt layer, the electrical conductivity of the metal is strongly modulated when interacting with chemical analytes, due to charges being transferred to/from Pt. The strong interaction with chemical species, together with the scalability of the material, enables the fabrication of chemiresistor devices for electrical read‐out of chemical species with sub part‐per‐billion detection limits. This opens a route for resilient and high sensitivity chemical detection and can […]
Space communication: developing a one photon-per-bit receiver using near-noiseless phase-sensitive amplification
Phys.org September 17, 2020 Phase-sensitive optical amplifiers (PSAs) with their uniquely low noise figure of 0 dB promise to provide the best possible sensitivity for Gb/s-rate long-haul free-space links. An international team of researchers (Sweden, USA – MIT, UC San Diego, industry, Japan) demonstrate a novel approach using a PSA-based receiver in a free-space transmission experiment with an unprecedented bit-error-free, black-box sensitivity of 1 photon-per-information-bit (PPB) at an information rate of 10.5 Gb/s. The system adopts a simple modulation format (quadrature-phase-shift keying, QPSK), standard digital signal processing for signal recovery and forward-error correction and is straightforwardly scalable to higher data rates…read more. […]
Turbulence affects aerosols and cloud formation
Science Daily September 16, 2020 Traditionally the mechanics of cloud formation have not accounted for turbulence. Researchers at the Michigan Technological University investigated the aspects of cloud formation under controlled conditions including the effects of fluctuations, produced by turbulence. The measurements show a clear transition from a regime in which the mean saturation ratio dominates to one in which the fluctuations determine cloud properties. Measurements in the chamber show that turbulence can mimic the behaviors that have been attributed to particle variation, primarily size and composition. According to the researchers their model will help forecasters predict the fluctuations Planet Ocean-Cloud […]
Volcanic ash may have a bigger impact on the climate than we thought
Science Daily September 11, 2020 After the Mt. Kelut eruption in 2014 on the island of Java, stratospheric ash-rich aerosols were observed for months. A team of researchers in the US (University of Colorado, NOAA, industry) shows that the persistence of super-micron ash is consistent with a density near 0.5 g cm−3, close to pumice. Ash-rich particles dominate the volcanic cloud optical properties for the first 60 days. They found that the initial SO2 lifetime is determined by SO2 uptake on ash, rather than by reaction with OH as commonly assumed. About 43% more volcanic sulfur is removed from the stratosphere in […]
Top 10 Science and Technology Inventions for the Week of September 11, 2020
01. Seeing objects through clouds and fog 02. Painting with light: Novel nanopillars precisely control intensity of transmitted light 03. Paving the way for tunable graphene plasmonic THz amplifiers 04. Quantum light squeezes the noise out of microscopy signals 05. Scientists predicted new hard and superhard ternary compounds 06. Superconductors are super resilient to magnetic fields 07. Terahertz receiver for 6G wireless communications 08. Chemists develop a new type of one-molecule thick water-repellent film 09. Swarming locusts inspire new collision detector 10. Nanoearthquakes control spin centers in SiC And others… BATTERY 2030+ – large-scale European initiative for battery research starts […]
BATTERY 2030+ – large-scale European initiative for battery research starts up
EurekAlert September 9, 2020 BATTERY 2030+ is a EU Horizon 2020 funded project led by Sweden. The goal is to create more environmentally friendly and safer batteries with better performance, greater storage options and longer life. The current research projects are operating in three different areas: I. Development of a European infrastructure platform to combine large-scale calculations and experimental studies to map the complex reactions that take place in a battery. II. Development and integration of sensors that examine and report on the battery’s health in real time. III. Development of self-healing components that extend battery life and improve safety…read more.
Chemists develop a new type of one-molecule thick water-repellent film
Nanowerk September 9, 2020 An international team of researchers (Russia, Belarus) developed 0.8-1.5 nm thick calixarene-based films that can work as water-repellent coatings. Calixarenes are large bowl-shaped organic molecules that consist of several rings. The outer ring of the bowl is hydrophilic, and the innermost ring is hydrophobic. Their durability can be increased with UV radiation. The films can be used to create protective hydrophobic or anti-corrosion coatings for organic electronics or to develop molecular filters…read more. TECHNICAL ARTICLE