Phys.org January 31, 2022 Using trapped-ion platform and optical tweezers researchers in the Netherlands have constructed new building blocks for quantum computing that pose fewer technical difficulties than current state-of-the art methods. Since the electric field allows for long-range qubit-qubit interactions mediated by the center-of-mass motion of the ion crystal alone, it is inherently scalable to large ion crystals. The proposed scheme does not rely on ground-state cooling. They studied the effects of imperfect cooling of the ion crystal, as well as the role of unwanted qubit-motion entanglement, and discuss the prospects of implementing the state-dependent tweezers in the laboratory… […]
New power transfer technology provides unprecedented freedom for wireless charging
Science Daily February 1, 2022 Using electromagnetics researchers in Finland have developed a free-positioning wireless power transfer technology that can direct power to individual devices without needing plugs, tracking devices , or complex computing. Devices can be charged while they are moving. Multiple transmitters (Txs) are placed in a pad-like area, and the transmitter coils are optimally excited to enable robust and efficient power transfer to movable receivers within the charging area. The configuration enables almost continuous magnetic flux path from a set of Tx coil(s) to another set of Tx coil(s) through the receiver coil ferrite core ensuring efficient […]
Physicists manipulate magnetism with light
Nanowerk January 28, 2022 The non-equilibrium driving of dressed quasiparticles offers a promising platform for realizing unconventional many-body phenomena and phases beyond thermodynamic equilibrium. An international team of researchers (USA – MIT, South Korea) achieved this in the van der Waals correlated insulator NiPS3 by photoexciting its newly discovered spin–orbit-entangled excitons that arise from Zhang-Rice states. By monitoring the time evolution of the terahertz conductivity, they observed the coexistence of itinerant carriers produced by exciton dissociation and a long-wavelength antiferromagnetic magnon that coherently processes in time. These results demonstrate the emergence of a transient metallic state that preserves long-range antiferromagnetism, […]
Power at sea: Towards high-performance seawater batteries
Science Daily January 31, 2022 Despite the many potential applications of seawater batteries (SWBs), the limited performance of available materials has hindered their commercialization. Researchers in South Korea have developed a process called ‘plasma in liquid,’ which involves preparing a mixture of precursors containing carbon, N, and S and discharging plasma into the solution resulting in a material with high doping levels of N and S with a structural backbone of carbon black. Experimentally they have confirmed that the material showed great potential for SWBs. The co-doped anode material exhibited remarkable electrochemical performance in SWBs, with a cycling life of […]
Scientists develop insect-sized flying robots with flapping wings
Science Daily February 2, 2022 Current flapping MAVs require transmission systems between their actuators and wings, which introduce energetic losses and additional mass, hindering performance. Researchers in the UK have developed a high-performance electrostatic flapping actuation system, the liquid-amplified zipping actuator (LAZA), which induces wing movement by direct application of liquid-amplified electrostatic forces at the wing root, eliminating the requirement of any transmission system and their associated downsides. Thrust up to 5.73 millinewtons was achieved while consuming only 243 milliwatts of electrical power, implying a thrust-to-power ratio of 23.6 newtons per kilowatt, like state-of-the-art flapping MAVs, helicopter rotors, and commercial […]
Scientists weave atomically thin wires into ribbons
Phys.org January 31, 2022 Using tungsten telluride nanowires researchers in Japan created bundles of wires deposited on a flat substrate and exposed to vapors of chalcogens like sulfur, selenium, and tellurium. With a combination of heat and vapor, the initially separate threads in the bundles were successfully woven together into narrow, atomically thin nanoribbons with a characteristic zigzag structure. By tuning the thickness of the original bundles, they could even choose whether these ribbons were oriented parallel to the substrate or perpendicular to it. By tuning the substrate on which the bundles are placed, they could control whether the ribbons […]
Tiny materials lead to a big advance in quantum computing
MIT News January 27, 2022 An international team of researchers (USA – MIT, MIT Lincoln Laboratory, Japan) used hexagonal boron nitride to build a parallel-plate capacitor for a qubit. To fabricate the capacitor, they sandwiched hexagonal boron nitride between very thin layers of another van der Waals material, niobium diselenide and connected the capacitor to the existing structure and cooled the qubit to 20 millikelvins (-273.13 C). The resulting qubit was about 100 times smaller than what they made with traditional techniques on the same chip. The coherence time, or lifetime, of the qubit was only a few microseconds shorter […]
Wide-visible-light-responsive photocatalyst boosts solar water splitting
Phys.org January 31, 2022 Bismuth vanadate (BiVO4) has been widely investigated as a photocatalyst or photoanode for solar water splitting, but its activity is hindered by inefficient cocatalysts and limited understanding of the underlying mechanism. An international team of researchers (China, Japan) demonstrated significantly enhanced water oxidation on the particulate BiVO4 photocatalyst via in situ facet-selective photodeposition of dual-cocatalysts that exist separately as metallic Ir nanoparticles and nanocomposite of FeOOH and CoOOH (denoted as FeCoOx), as revealed by advanced techniques. The mechanism of water oxidation promoted by the dual-cocatalysts is experimentally and theoretically unraveled, and mainly ascribed to the synergistic […]
Top 10 Science and Technology Inventions for the Week of January 28, 2022
01. A new record for laser stability across atmospheric distances 02. Team demonstrates molecular electronics sensors on a semiconductor chip 03. Just listen to the chaos: A new approach to extracting information from large ensembles of sensors 04. A leap forward for terahertz lasers 05. Researchers find new way of gaining quantum control from loss 06. Scientists simulate ‘fingerprint’ of noise on quantum computer 07. Sunlight could be used to power lasers 08. Harnessing noise in optical computing for AI 09. Development of a lithium-air battery with an energy density over 500 wh/kg 10. Twin-field quantum key distribution (QKD) across […]
Development of a lithium-air battery with an energy density over 500 wh/kg
Science Daily January 20, 2022 Lithium–air batteries (LABs) are potential candidates for next-generation rechargeable batteries because of their extremely high theoretical energy density. However, the reported values for the actual energy density of LABs are much lower than those for lithium batteries, mainly due to the excess amount of electrolyte in the cell. In the present review article, researchers in Japan estimated the practical energy density for the representative LABs reported in academia, and the critical factors for improving the energy density of LABs are summarized. The criteria for evaluating LABs in laboratory-based experiments are also proposed for accurately predicting […]