Phys.org June 2, 2021 An international team of researchers (USA – NIST, Jet Propulsion Laboratory, MIT, UK) has developed superconducting nanowire single-photon detectors based on tungsten silicide. To compensate for the lower energy carried by IR light they reduced the density of electrons in the wires that are available to absorb the photons. With fewer electrons available, the fraction of the total photon energy absorbed by any one electron is likely to be higher, increasing the likelihood that the electron would have enough energy to cross the superconducting gap and generate a signal when IR photons strike the detector. They […]
DNA circuits
EurekAlert June 2, 2021 Researchers in China have developed a configurable, multi-mode logic switching network that reacts differently with its surroundings depending on pH and DNA input. They developed a series of four DNA switches, each with slightly different lengths and combinations of bases. At a slightly alkaline pH of 8, two of the switches formed triple-stranded DNA, while the others remained loosely stretched out. These reactions and folds led to secondary reactions, which were utilized by the researchers as logic functions in the switching circuit. In demonstration DNA acted as a crosslinker, joining the polymer molecules in the gel […]
Making batteries live longer with ultrathin lithium
Phys.org June 1, 2021 Lithium metal batteries (LMBs) have high energy density that exceeds lithium batteries (LIBs) by an order of magnitude. The key difference lies in the choice of anode material: LIBs use graphite leading to the formation of dendrites, whereas LMBs use lithium metal. Researchers in South Korea adopted a novel approach in which they pre-planted LiNO3 in the lithium metal powder (LMP) itself during the electrode fabrication process, allowing them to fabricate ~150-mm-wide and 20-μm-thick electrodes, which showed a coulombic efficiency of 96%. The addition of LiNO3 to LMP accomplished two things: it induced a uniform N-rich […]
Mapping zoonotic ‘hot spots’ where risk of coronaviruses jumping from bats to humans is highest
Phys.org June 1, 2021 The extent to which humans facilitate zoonotic transmission of infectious diseases is unclear. Human encroachment into wildlife habitats, cropland area and intensive animal farming is hypothesized to favour the emergence of zoonotic diseases. An international team of researchers (Italy, USA – UC Berkeley, New Zealand) analysed comprehensive, high-resolution datasets on forest cover, cropland distribution, livestock density, human population, human settlements, bat species’ distribution and land-use changes in regions populated by Asian horseshoe bats (>28.5 million km2)—the species that most commonly carry severe acute respiratory syndrome (SARS)-related coronaviruses. They identified areas at risk of SARS-related coronavirus outbreaks, showing that […]
A new direction of topological research is ready for take off
Phys.org June 1, 2021 An international team of researchers (Germany, Italy, USA – University of Maryland) has accomplished synthetic topological matter in electric circuit networks. The main motif of topological matter is its role in hosting particularly stable and robust features immune to local perturbations, which might be a pivotal ingredient for future quantum technologies. The current results promise a knowledge transfer from electric circuits to alternative optical platforms. Topolectric circuits create an experimental and theoretical inspiration for new avenues of topological matter and might have a particular bearing on future applications in photonics. The flexibility, cost-efficiency, and versatility of […]
Newly identified atmospheric circulation enhances heatwaves and wildfires around the Arctic
Phys.org June 2, 2021 An international team of researchers (Japan, USA – NASA Goddard Space Flight Center, South Korea) assessed comprehensive air pollution (PM2.5) in the Arctic for the past 15 years to clarify the relationships between variations in PM2.5 and aerosols, wildfires, and the relevant climate patterns. They found 13 out of the 20 months with highest PM2.5 in the Arctic during the 15-year period were in summer. The elevated PM2.5 levels were highly correlated with relatively higher organic carbon aerosol concentrations, implying active wildfires. In those months, the wildfires likely occurred under extremely warm and dry conditions. Those […]
Quantum computing with holes
Phys.org June 3, 2021 An international team of researchers (Austria, Italy, Germany, Spain) has created a new candidate system for reliable qubits using the spin of holes which carry the quantum-mechanical property of spin and interact if they come close to each other. The hole can move around in the solid when a neighboring electron fills the hole. They confined the holes to the germanium-rich layer in the middle of layered silicon and germanium adding gates to control the movement of holes. They could move holes and alter their properties. By engineering different hole properties, they created the qubit out […]
Scientists unravel noise-assisted signal amplification in systems with memory
Phys.org May 27, 2021 Signals can be amplified by an optimum amount of noise, but stochastic resonance (SR) is a fragile phenomenon. To investigate the role of memory for this phenomenon an international team of researchers (the Netherlands, UK) used an oil-filled microcavity which, driven by a continuous wave laser, has memory in its nonlinear optical response. Modulating the cavity length while adding noise to the driving laser, they observed a peak in the transmitted signal-to-noise ratio as a function of the noise variance. Through simulations, they reproduced their observations and extrapolated that the SR bandwidth could be approximately 3000 […]
Shadow figment technology foils cyberattacks
Science Daily June 2, 2021 Researchers at the Pacific Northwest National Laboratory have created a cybersecurity technology called Shadow Figment which uses artificial intelligence to deploy elaborate deception to keep attackers engaged in a pretend world — the figment — that mirrors the real world. The decoy interacts with users in real time, responding in realistic ways to commands. It rewards hackers with false signals of success, keeping them occupied while defenders learn about the attackers’ methods and take actions to protect the real system. The credibility of the deception relies on a machine learning program that learns from observing […]
Weird Electromagnetic Bursts Appear Before Earthquakes – And We May Finally Know Why
Science Alert May 30, 2021 Seismologists have been aware of brief, subtle anomalies in underground electrical fields leading up to an earthquake, sometimes occurring as soon as a few weeks before the quake happens. Research suggests that when gases interact with newly created crack surfaces, the unpaired electrons within the rock crystal defects are thermally stimulated, released into the crack due to the temperature rise at the crack tip via plastic work, and attached to ambient gas molecules to electrify them in a negative state. Researchers in Japan used a customized lab setup to test the reactions of quartz diorite, […]