01. Chaining atoms together yields quantum storage 02. An innovative technology for 6G communication networks 03. It’s in the air – battery discovery takes up the charge 04. Researchers combine piezoelectric thin film and metasurfaces to create lens with tunable focus 05. Researchers use solar cells to achieve fast underwater wireless communication 06. Researchers create molecule that can pave way for mini transistors 07. Two-dimensional material could store quantum information at room temperature 08. Researchers identify mechanism by which fatigue cracks grow 09. Solar-powered system offers a route to inexpensive desalination 10. Squeezing the noise out of microscopes with quantum […]
Chaining atoms together yields quantum storage
Phys.org February 16, 2022 Researchers at Caltech have developed an approach for quantum storage that relies on nuclear spins oscillating collectively as a spin wave. This collective oscillation effectively chains up several atoms to store information. They utilized a qubit made from an ion of ytterbium and embedded the ion in a transparent crystal of yttrium orthovanadate (YVO4) and manipulated its quantum states via a combination of optical and microwave fields. The Yb qubit was used to control the nuclear spin states of multiple surrounding vanadium atoms in the crystal. A unique feature of this system is the pre-determined placement […]
Fabrication of perovskite solar cells with just a piece of paper? A new method tells you how! (w/video)
Nanowerk February 15, 2022 Most perovskite films in laboratories around the world are deposited through spin coating which guarantees high control on film thickness as well as morphology. However, most of the ink is expelled during deposition and wasted. An international team of researchers (Iran, Italy) has developed a completely new method that uses a simple sheet of paper to deposit the perovskite films without a spin coater or other large area techniques such as slot-die coating or blade coating. They fabricated solar cells on flexible PET substrates manually with 11% power conversion efficiency. Deposition after soaking the sheet of […]
Graphene spintronics: 1D contacts improve mobility in nano-scale devices
Science Daily February 11, 2022 An international team of researchers (UK, Japan) used monolayer graphene encapsulated by hexagonal boron nitride in van der Waals heterostructure with one-dimensional contacts. They measured electron mobility up to 130,000cm2/Vs at low temperatures (20K or -253oC) and spin diffusion lengths approaching 20 μm. The nanoscale-wide 1D contacts allow spin injection both at room and at low temperature, with the latter exhibiting efficiency comparable with 2D tunnel contacts. At low temperature, the spin signals can be enhanced by as much as an order of magnitude by electrostatic gating, adding new functionality. According to the researchers the […]
An innovative technology for 6G communication networks
Science Daily February 15, 2022 Terahertz waveguides are required to provide versatile signal-processing functionalities. Despite fundamental components they typically rely on complex hybridization, in turn making it extremely challenging to go beyond the most elementary functions. An international team of researchers (Canada, Italy, Germany) has proposed a universal approach, in which multiscale-structured Bragg gratings can be directly etched on metal-wires. They designed a four-wire waveguide geometry, amenable to support the low-loss and low-dispersion propagation of polarization-division multiplexed terahertz signals. By engraving on the wires judiciously designed Bragg gratings based on multiscale structures, they demonstrated that it is possible to independently […]
It’s in the air – battery discovery takes up the charge
Science Daily February 10, 2022 An international team of researchers (Australia, China, USA – Argonne National Laboratory) describe the details of an Li-O2 battery operated via a new quenching/mediating mechanism that relies on the direct chemical reactions between a versatile molecule and superoxide radical/Li2O2. The battery exhibits a 46-fold increase in discharge capacity, a low charge overpotential of 0.7 V, and an ultralong cycle life greater than 1400 cycles. Redox-active 2,2,6,6-tetramethyl-1-piperidinyloxy moieties bridged by a quenching-active perylene diimide backbone acts as a redox mediator to catalyze discharge/charge reactions and serves as a reusable superoxide quencher to chemically react with superoxide […]
New plant-derived composite is tough as bone and hard as aluminum
MIT News February 10, 2022 So far researchers have been able to incorporate low fractions of the exceptionally strong carbon nanocrystals (CNCs), as the crystals tend to clump and only weakly bond with polymer molecules. To develop a composite with a high fraction of CNCs researcher at MIT determined the ratio of CNC and polymer that would turn the solution into a gel, with a consistency that could either be fed through the nozzle of a 3-D printer or poured into a mold to be cast. When dried the material shrank, leaving behind a solid composite composed mainly of cellulose […]
A proposal to use electric charges to encourage raindrops to form in clouds
Phys.org February 9, 2022 Researchers in the UK calculated the electrostatic forces between two water spheres that have not yet grown large enough to be described as raindrops. They found that the greater the variation in charges between droplets, the stronger the attraction between them. And that led them to suggest that if the variation was increased via an electric charge, the droplets would merge, leading to the formation of rain drops. As droplets merge and grow in size, additional electric charge should result in mergers between droplets until they become large enough for gravity to take over and they […]
Researchers combine piezoelectric thin film and metasurfaces to create lens with tunable focus
EurekAlert February 17, 2022 Using metasurfaces researchers in Norway designed a device in which a metasurface is suspended on a membrane ring made of a thin-film lead zirconate titanate (PZT) film, which allows the PZT to move the metasurface when a voltage is applied. To demonstrate how MEMS-metasurfaces could function as a varifocal lens doublet, they placed a second metasurface lens after the MEMS-metasurface. Varying the separation distance between the lenses through MEMS displacement allowed researchers to tune the focal point of the lens doublet on the fly. The researchers showed that applying 23 volts allowed the PZT membrane to […]
Researchers use solar cells to achieve fast underwater wireless communication
Science Daily February 16, 2022 The greatest problem in using solar panels for underwater wireless optical communication (UWOC) systems is the limited bandwidth of the solar panel, which was originally optimized for energy harvesting rather than communication. Researchers in China studied the fundamentals of the solar array and proposed series-connected solar arrays for high-speed underwater detection. As they increased the size of the solar array from 1×1 to 3×3, the −20-dB bandwidth increased from 4.7 MHz to 24.2 MHz. To further improve the frequency response, they applied a reverse bias on the array. With a reverse bias voltage of 90 […]