EurekAlert March 6, 2024 Optical properties of afterglow luminescent particles (ALPs) in mechanoluminescence (ML) and mechanical quenching (MQ) have diverse technological applications. An international team of researchers (South Korea, USA – Stanford University) designed ALPs for the development of a wearable and rewritable photonic display system as a communication toolbox under dark conditions or underwater environments with limited communication. The system demonstrated long-lasting MQ after short ML along the handwritten trajectories with mechanical pressure and the written content could be easily erased by short UV light irradiation, preserving the system integrity with the high reproducibility of ML and MQ responses. […]
Preventing magnet meltdowns before they can start
Science Daily March 11, 2024 Unlike conventional magnets where a normal zone expands typically quickly, and the stored energy is dissipated across a large volume of the windings, a normal zone in a High-temperature superconductor (HTS) magnet propagates slowly and, thus, can heat up quickly to high temperatures destroying the conductor. At the same time, growing experimental evidence suggests that HTS conductors can operate in a stable dissipative flux flow regime for a substantial range of operational currents before entering an irreversible thermal runaway. Researchers at Lawrence Berkeley National Laboratory proposed a simple criterion for the thermal runaway in HTS […]
Researchers achieve quantum key distribution for cybersecurity in novel experiment
Phys.org March 13, 2024 In their conference paper researchers at Oak Ridge National Laboratory reported on the first implementation of their CV-QKD scheme over a deployed optical fiber network. According to the researchers, in continuous variable quantum key distribution (CV-QKD), using a truly local (not transmitted over the network) oscillator improves security… read more. TECHNICAL ARTICLE
Researchers find exception to 200-year-old scientific law governing heat transfer
Phys.org March 4, 2024 Researchers at UMass, Amherst, revisited the Fourier’s law for heat transfer and transport within translucent materials. They compared the model predictions to infrared-based measurements with nearly mK temperature resolution. After heat pulses, they found macroscale non-Gaussian tails in the surface temperature profile. At steady state, they found macroscale anomalous hot spots when the sample was topographically rough. These discrepancies from Fourier’s law for translucent materials suggested that internal radiation whose mean-free-path is millimeters interacted with defects to produce small heat sources that by secondary emission afford an additional, non-local mode of heat transport. According to the […]
Researchers generate super-fast electrons with table-top laser systems
Phys.org March 13, 2024 MeV temperature electrons generation at non-relativistic intensities with high repetition rate lasers is important for the realization of compact, ultra-fast electron sources. An international team of researchers (India, UK, China) developed a technique of dynamic target structuring of micro-droplets using a millijoule class laser that used two collinear laser pulses; the first to create a concave surface in the liquid drop and the second, to dynamically-drive electrostatic plasma waves that accelerated electrons to MeV energies. The acceleration mechanism, identified as two plasmon decay instability was shown to generate two beams of electrons with hot electron temperature […]
You don’t need glue to hold these materials together—just electricity
Phys.org March 13, 2024 Researchers at the University of Maryland discovered that hard, electrical conductors (e.g., metals or graphite) could be adhered to soft, aqueous materials (e.g., hydrogels, fruit, or animal tissue) by a low DC electric field. They applied 5 V DC to graphite slabs spanning a tall cylindrical gel of acrylamide which resulted in a strong adhesion between the anode (+) and the gel in about 3 min. This adhesion lasted after the field was removed. They called it hard–soft electroadhesion or EA[HS]. Depending on the material, adhesion occurred at the anode (+), cathode (−), or both electrodes. […]
Top 10 Science and Technology Inventions for the Week of March 8, 2024
01. Designing a drone that uses adaptive invisibility: Towards autonomous sea-land-air cloaks 02. New class of 2D material displays stable charge density wave at room temperature 03. Research team develops a wireless sensor for spotting chemical warfare agents 04. Researchers create new compound to build space-age antennas 05. Scientists launch hub to channel quantum power for good 06. Tests show high-temperature superconducting magnets are ready for fusion 07. Zero-index metamaterials and the future 08. Making quantum bits fly 09. Research team develops a more durable coating against ice 10. Researchers provide unprecedented view into aerosol formation in Earth’s lower atmosphere […]
Better neutron mirrors can reveal the inner secrets of matter
Science Daily February 29, 2024 The state-of-the-art multilayer polarizing neutron optics has limitations, particularly low specular reflectivity and polarization at higher scattering vectors/angles, and the requirement of high external magnetic fields to saturate the polarizer magnetization. An international team of researchers (Sweden, Iceland, Switzerland, Germany) showed that, by incorporating 11B4C into Fe/Si multilayers, amorphization and smooth interfaces could be achieved, yielding higher neutron reflectivity, less diffuse scattering, and higher polarization. Magnetic coercivity was eliminated, and magnetic saturation could be reached at low external fields. According to the researchers this approach offered prospects for substantial improvement in polarizing neutron optics with […]
Correlation spectroscopy research shows network of quantum sensors boosts precision
Phys.org March 4, 2024 The coherence time of the quantum system surpasses that of the oscillator probing the system. Correlation spectroscopy overcomes this limitation by probing two quantum systems with the same noisy oscillator for a measurement of their transition frequency difference enabling very precise comparisons of atomic clocks. An international team of researchers (Austria, Israel, USA – Caltech) extended correlation spectroscopy to the case of multiple quantum systems undergoing strong correlated dephasing. They modelled Ramsey correlation spectroscopy with N particles as a multiparameter phase estimation problem and demonstrated that multiparticle correlations could assist in reducing the measurement uncertainties even […]
Designing a drone that uses adaptive invisibility: Towards autonomous sea-land-air cloaks
Phys.org March 6, 2024 An omnidirectional flying cloak has not been achieved so far, primarily due to the challenges associated with dynamic synthesis of metasurface dispersion. Researchers in China have demonstrated an autonomous aero amphibious invisibility cloak that incorporated a suite of perception, decision, and execution modules, capable of maintaining invisibility amidst kaleidoscopic backgrounds and neutralizing external stimuli… read more. Open Access TECHNICAL ARTICLE