Phys.org July 26, 2021 A team of researchers in the US (Virginia Tech, UC Santa Barbara) created a de-icing method based on Cassie’s Law, which shows that air can be trapped under water drops if the drops are suspended atop a structure that is bumpy and water-repellent. They sought to make ice form in a layer with lower adhesion to the surface. They created an array of pillars, each one millimeter tall by half a millimeter wide. The tiny pedestals were machined into a pattern with a millimeter between the pillars. As the temperature dropped, frost preferentially grew on the […]
New quantum research gives insights into how quantum light can be mastered
Phys.org July 22, 2021 Researchers at Los Alamos National Laboratory propose that modulated quantum metasurfaces can control all properties of photonic qubits, a breakthrough that could impact the fields of quantum information, communications, sensing and imaging, as well as energy and momentum harvesting. They developed a metasurface that looked like an array of rotated crosses, then proposed to shoot a single photon through the metasurface, where the photon splits into a superposition of many colors, paths, and spinning states generating quantum entanglement meaning the single photon can inherit different properties at once. According to the researchers by manipulating these properties, […]
The quantum refrigerator
Science Daily July 29, 2021 An international team of researchers (Germany, Austria, Portugal, Singapore) has provided a detailed proposal of how to realize a quantum machine in one-dimensional ultracold atomic gases, which consists of a set of modular operations giving rise to a piston. These can then be coupled sequentially to thermal baths, with the innovation that a quantum field takes up the role of the working fluid. They proposed models for compression on the system to use it as a piston and coupling to a bath that gives rise to a valve controlling heat flow. By composing the numerically […]
Spin-sonics: Acoustic wave gets the electrons spinning
Phys.org July 29, 2021 An international team of researchers (Germany, Canada, USA – Perdue University) has detected the rolling movement of a nano-acoustic wave predicted by Lord Rayleigh in 1885. They used an extremely fine nanowire that was positioned on lithium niobate, a piezoelectric material, which becomes deformed when subjected to an electrical current. With the aid of small metal electrodes, an acoustic wave can be generated on the material. The acoustic wave generates an elliptically rotating electrical field. This, in turn, forces the electrons in the nanowire onto circular paths. So far, this phenomenon was seen in light. Now […]
Through the thin-film glass, researchers spot a new liquid phase
Phys.org July 27, 2021 The structure of a glass closely resembles the liquid phase, but its properties are like solids, akin to a crystal. In vapor deposition, a material is changed from a gas into a solid directly. Researchers at the University of Pennsylvania used vapor deposition to create very dense thin-film glasses, corresponding to the packing of the new liquid phase, with a density much higher than was predicted to be possible without applying immense amounts of pressure. Thin films of these glasses can have density values even higher than crystal. Detailed structural information analysis of how individual molecules […]
Tracking the movement of a single nanoparticle
Phys.org July 27, 2021 Researchers in South Korea have developed a fluorescence-based nanoparticle tracking analysis (NTA) system to characterize the size and protein expression of individual extracellular vesicles (EV). In this system, a sheet of lasers with four different wavelengths was shone onto the EVs according to a programmed schedule, providing scattering images intercalated by three fluorescent images. The size, ratio, and scattered light of thousands of individual particles were observed, and a six-dimensional value composed of three different fluorescence was obtained. They measured the distribution of specific proteins in EVs (e.g., exosomes) at individual particle levels and analyzed the […]
Wirelessly charging multiple devices simultaneously
Science Daily July 27, 2021 A transmitter traditionally must first detect a device presence and position to be able to send energy in its direction. Researchers in Finland have designed a proof-of-concept device which creates power transfer channels in all directions, automatically tuning channels when receiving devices are in motion. Because of self-tuning, the device does not need complex electronics to connect with receivers embedded in devices and it can be moved freely within a wide charging range. By winding the coils in a specific way, they created two kinds of electromagnetic fields: one going outwards and the other around. […]
Top 10 Science and Technology Inventions for the Week of July 23, 2021
01. Low-cost, sustainable, readily available plasma technology could replace one of the world’s 02. The paradox of a free-electron laser without the laser 03. Achilles heel of graphene exposed 04. Future information technologies: Topological materials for ultrafast spintronics 05. Microbially produced fibers: Stronger than steel, tougher than Kevlar 06. Making clean hydrogen is hard, but researchers just solved a major hurdle 07. Nanostructures enable record high-harmonic generation 08. New material could mean lightweight armor, protective coatings 09. Scientists create rechargeable swimming microrobots using oil and water 10. The era of single-spin color centers in silicon carbide is approaching And others… […]
Achilles heel of graphene exposed
Nanowerk July 19, 2021 The quantum Hall effect is the seminal example of topological protection as charge carriers are transmitted through one-dimensional edge channels where backscattering is prohibited. In conventional Hall bar geometries, topological protection of graphene edge channels is found less robust than in high mobility semi-conductors. An international team of researchers (Belgium, Germany, Japan) exploring graphene quantum Hall regime at the local scale revealed that the detrimental influence of antidots along the graphene edges, mediating backscattering towards upstream edge channels triggering topological breakdown. The finding is a major step forward in the understanding of the quantum Hall effect […]
The era of single-spin color centers in silicon carbide is approaching
Phys.org July 19, 2021 The spin color centers in silicon carbide, including silicon vacancies and divacancies have excellent optical and spin properties. Researchers in China have presented the coherent manipulation of single divacancy spins in 4H-SiC with a high readout contrast (−30%) and a high photon count rate under ambient conditions, which are competitive with the nitrogen-vacancy centres in diamond. Coupling between a single defect spin and a nearby nuclear spin is also observed. They provided a theoretical explanation for the high readout contrast by analysing the defect levels and decay paths. Since the high readout contrast is important in […]