Phys.org June 16, 2023 Quantum circuits interact with the environment via several temperature-dependent degrees of freedom. Multiple experiments to-date have shown that most properties of superconducting devices appear to plateau out at T ≈ 50 mK – far above the refrigerator base temperature. This is reflected in the thermal state population of qubits and polarisation of surface spins. An international team of researchers (UK, Sweden, USA – industry) demonstrated how to remove this thermal constraint by operating a circuit immersed in liquid 3He. This allowed cooling tof he decohering environment of a superconducting resonator. They saw a continuous change in measured physical […]
New research on self-locking light sources presents opportunities for quantum technologies
Nanowerk June 19, 2023 An international team of researchers (Argentina, Germany) demonstrated that light emitters with different resonance frequencies can asynchronously self-lock their relative energies by exchanging mechanical energy. They introduced polaromechanical metamaterials, two-dimensional arrays of μm-sized traps confining zero-dimensional light-matter polariton fluids and GHz phonons. A strong exciton-mediated polariton-phonon interaction induced a time-dependent inter-site polariton coupling J(t) with remarkable consequences for the dynamics. When locally perturbed by continuous wave optical excitation, a mechanical self-oscillation started and polaritons responded by locking the energy detuning between neighbor sites at integer multiples of the phonon energy showing asynchronous locking involving the polariton […]
Researchers develop a current collector for energy storage devices with high-efficiency and long cycling life
Nanowerk June 21, 2023 Researchers in South Korea used to prepare floating catalyst–chemical vapor deposition-derived CNT sheets for potential use as all-around current collectors in two representative energy storage devices: batteries and electrochemical capacitors. CNT-based current collectors enhance ion transport kinetics and provide many ion adsorption and desorption sites, which are crucial for improving the performance of batteries and electrochemical capacitors. They demonstrated high-performance lithium-ion hybrid capacitors (LIHCs) by assembling activated carbon–CNT cathodes and prelithiated graphite–CNT anodes. CNT-based LIHCs exhibit 170% larger volumetric capacities, 24% faster rate capabilities, and 21% enhanced cycling stabilities relative to LIHCs based on conventional metallic […]
Researchers develop an extreme environment-resistant nanopaper
Phys.org June 21, 23 Researchers in China developed a kind of nacre-inspired bacterial cellulose (BC)/synthetic mica (S-Mica) nanopaper with excellent mechanical and electrical insulating properties that has excellent tolerance to extreme conditions. The nanopaper exhibited excellent mechanical properties, including high tensile strength (375 MPa), outstanding foldability, and bending fatigue resistance. S-Mica arranged in layers endowed the nanopaper with remarkable dielectric strength (145.7 kV mm−1) and ultralong corona resistance life. The nanopaper was highly resistant to alternating high and low temperatures, UV light, and atomic oxygen… read more. TECHNICAL ARTICLE
This salty gel could harvest water from desert air
MIT News June 15, 2023 Hygroscopic hydrogels are emerging as scalable and low-cost sorbents for atmospheric water harvesting, dehumidification, passive cooling, and thermal energy storage. However, devices using these materials still exhibit insufficient performance, partly due to the limited water vapor uptake of the hydrogels. Researchers in Germany synthesized hygroscopic hydrogels with extremely high salt loadings by tuning the salt concentration of the swelling solutions and the cross-linking properties of the gels. This resulted in unprecedented water uptakes at relative humidity. At 30% RH, the uptake exceeded previously reported water uptakes of metal–organic frameworks by over 100% and of hydrogels […]
Scientific fraud is rising, and automated systems won’t stop it. We need research detectives
Phys.org June 21, 223 A group of multidisciplinary scientists are working to tackle research fraud and poor practice using metascience. Fraud in science is alarmingly common – sometimes researchers lie about results and invent data to win funding and prestige, researchers might pay to stage and publish entirely bogus studies to win an undeserved pay rise—fueling a “paper mill” industry worth an estimated €1 billion a year. More sophisticated AI which can generate plausible scientific data is a new threat. Some of this can be easily spotted by peer reviewers, but the peer review system has become badly stretched by […]
Treatment creates steel alloys with superior strength and plasticity
Science Daily June 14, 2023 Nanostructured metallic materials with abundant high-angle grain boundaries exhibit high strength and good radiation resistance. While the nanoscale grains induce high strength, they also degrade tensile ductility. A team of researchers in the US (Purdue University, Sandia National Laboratory) showed that a gradient nanostructured ferritic steel exhibited simultaneous improvement in yield strength by 36% and uniform elongation by 50% compared to the homogenously structured counterpart. In situ tension studies coupled with electron backscattered diffraction analyses revealed intricate coordinated deformation mechanisms in the gradient structures. The outermost nanolaminate grains sustained a substantial plastic strain via a […]
Trillionths of a second: Photon pairs compress an electron beam into short pulses
Phys.org June 19, 2023 Researchers in Germany used nonlinear-optical two-photon transitions for the quantum-coherent control of a free-electron matter wave in free space. They superimposed an electron beam with two crossed laser beams of different photon energies for non-linear Compton scattering. At suitable angle combinations, the electron energy spectrum became modulated into discrete energy sidebands with thousands of interference maxima. They explained their observations by the cascaded addition and subtraction of two-photon pairs under three-body conservation of energy and momentum. Calculations revealed that the electron matter wave converted into pulses of few-attosecond duration. According to the researchers their work provides […]
With trapped waves, researchers resolve a longstanding debate
Nanowerk June 17, 2023 Anderson localization is the absence of diffusion of waves in disordered systems. Despite extensive studies over the past 40 years, Anderson localization of light in three dimensions has remained elusive, leading to the question of its very existence. An international team of researchers (USA – Missouri University, industry, University of Wisconsin, France) used brute-force numerical simulations of light transport in fully disordered three-dimensional systems with unprecedented dimension and refractive index difference. They showed numerically three-dimensional localization of vector electromagnetic waves in random aggregates of overlapping metallic spheres, in sharp contrast to the absence of localization for dielectric […]
Top 10 Science and Technology Inventions for the Week of June 16, 2023
01. Breaking through the limits of stretchable semiconductors with molecular brakes that harness light 02. Breakthrough: Scientists develop artificial molecules that behave like real ones 03. For experimental physicists, quantum frustration leads to fundamental discovery 04. Heat highways’ could keep electronics cool 05. Megawatt electrical motor designed by MIT engineers could help electrify aviation 06. New material transforms light, creating new possibilities for sensors 07. A new technique to detect invisibility cloaks 08. Researchers discover materials exhibiting huge magnetoresistance 09. Researchers tune thermal conductivity of materials ‘on the fly’ for more energy-efficient devices 10. Ultrafast and tunable: Graphene-based terahertz-to-visible light […]