Phys.org September 7, 2020 It was once assumed that the superconducting-to-normal transition caused by a magnetic field could not be reversed easily. However, it has been known for a long time from experiments that, if you remove the magnetic field, a current-carrying superconductor can, in fact, be returned to its previous state without loss of energy. Researchers in Japan proposed a new explanation for this phenomenon. In the superconducting state, electrons pair up and move in sync, but the true cause of this synchronized motion is due to Berry connection, characterized by the topological quantum number. It is an integer […]
Author Archives: Hema Viswanath
Swarming locusts inspire new collision detector
Physics World September 7, 2020 Collision avoidance models based on image processing algorithms have been implemented using analogue very-large-scale-integration designs, but none is as efficient as this neuron in terms of energy consumption or size. The lobula giant movement detector (LGMD) neuron in locusts can detect an approaching object and prevent collisions within a swarm of millions of locusts. This single neuronal cell performs nonlinear mathematical operations on visual stimuli to elicit an escape response with minimal energy expenditure. An international team of researchers (USA – Pennsylvania State University, India) developed a nanoscale collision detector that mimics the escape response […]
Terahertz receiver for 6G wireless communications
Phys.org September 8, 2020 Future 6G wireless networks will consist of a multitude of small radio cells that need to be connected by broadband communication links. An international team of researchers (Germany, USA – industry) has developed a novel concept for low-cost terahertz receivers that consist of a Schottky barrier diode that offers large bandwidth and that is used as an envelope detector to recover the amplitude of the terahertz signal. To overcome the problem of losing the time-dependent phase of the terahertz wave that is usually lost during rectification, they use digital signal processing techniques in combination with a […]
Top 10 Science and Technology Inventions for the Week of September 4, 2020
01. A molecular approach to quantum computing 02. Molecule to store solar energy developed 03. New electronic skin can react to pain like human skin 04. Researchers manipulate two bits in one atom 05. Revolutionary quantum breakthrough paves way for safer online communication 06. Single-Molecule Cloak 07. Stanford engineers reprogram yeast cells to become microscopic drug factories 08. These Underwater Drones Use Water Temperature Differences To Recharge 09. Memory in a metal, enabled by quantum geometry 10. Music goes terahertz: Scientists achieve breakthrough for pulsed terahertz lasers And others Giant Gaping Void Emerges in Siberia, The Latest in a Dramatic […]
Giant Gaping Void Emerges in Siberia, The Latest in a Dramatic Ongoing Phenomenon
Science Alert September 2, 2020 A bubble of methane gas, swelling beneath Siberia’s melting permafrost for who knows how long, has burst open to form an impressive 50-metre-deep (164-foot-deep) crater throwing chunks of ice and rock hundreds of metres away from the epicentre. It is not clear when the hole formed, or if climate change played a role. The giant holes are thought to result from the sudden collapse of hills, or swellings of tundra, which themselves form when melting permafrost causes a build-up of methane beneath the surface. Methane is 84 times more potent as a greenhouse gas than […]
Lightmatter’s Mars Chip Performs Neural-Network Calculations at the Speed of Light
IEEE Spectrum August 29, 2020 To perform neural-network calculations faster and more efficiently based on optical computing researchers in the US (industry) have built Mars device which has at its heart a chip that includes an analog optical processor, designed specifically to perform the mathematical operations that are fundamental to neural networks. The key optical processor is shrunk to nanometers and integrated them together on one chip for the purpose of speeding up neural-network calculations. The interferometer splits incoming light into two beams, which then take two different paths. The resulting two beams are then recombined. If the two paths […]
Memory in a metal, enabled by quantum geometry
Phys.org September 1, 2020 Previous research had shown that when tungsten ditelluride is in a topological state, the special arrangement of atoms in its layers can produce Weyl nodes which will exhibit unique electronic properties, such as zero resistance conduction. An international team of researchers (USA – UC Berkeley, Stanford University, Lawrence Berkeley National Laboratory, Texas A&M, South Korea) made odd numbered layers slide relative to even-number layers in tungsten ditelluride. The arrangement of these atomic layers represents 0 and 1 for data storage. They made use of Berry curvature to read information out. This material platform works ideally for […]
A molecular approach to quantum computing
Science Daily September 2, 2020 Researchers in the US (Caltech) applied the concept of error correction to rotating molecules in superposition. If the orientation or angular momentum of the molecule shifts by a small amount, those shifts can be simultaneously corrected. They constructed quantum error-correcting codes that embed a finite-dimensional code space in the infinite-dimensional Hilbert space of rotational states of a rigid body. They protect against both drift in the body’s orientation and small changes in its angular momentum. Hence, they may be well suited for robust storage and coherent processing of quantum information. They have described codes and […]
Molecule to store solar energy developed
Science Daily August 31, 2020 An international team of researchers (Sweden, Hungary, India) has developed a molecule belonging to the molecular photoswitches group that can take on two different forms: a parent form that can absorb energy from sunlight, and an alternative form where the structure of the parent form is changed to become much more energy-rich, while remaining stable. Through calculations they show that the molecule would undergo the desired change within 200 femtoseconds. The concept of switching between aromatic and non-aromatic states of a molecule has a major potential in the field of molecular photoswitches. A possible long-term […]
Moth-eye nanostructures make good anti-icing coatings
Physics World September 3, 2020 Researchers in Vietnam fabricated moth eye structure on the quartz substrate covered with a flat paraffin layer to isolate it in a cold and humid environment. The paraffin layer only stayed on the top of the nanostructure, separated it from the outside environment to obstruct heat energy being transferred to the cold substrate, and prevented the wetting transition, which was observed regularly on the rough surface. Numerous air blocks trapped inside the nanostructure also contributed to delayed heat transfer, leading to an increase in the freezing time of the attached water droplet. The nanostructure coated […]