Phys.org December 4, 2024 Researchers in Spain analyzed the stones collected during fieldwork to gather information on their growth processes. They analysed used Computed Tomography Scan, which was utilized to analyze hailstones and their interiors. They obtained a complete 3D view of the interior of the stone, without producing any alteration in the structure they quantified densities of different layers. The analysis helped verify previous theories that the nuclei can be placed far from the stone center even if the hailstone is externally spherical… read more. Open Access TECHNICAL ARTICLE
Tag Archives: S&T Spain
Scientists develop cost-effective lasers for extended short-wave infrared applications
Phys.org December 10, 2024 Currently, the spectral coverage of solution-processed lasers extends from visible up to telecom wavelengths in the short-wave infrared. Using lead sulphide based colloidal quantum dots researchers in Spain demonstrated the optical gain in the extended SWIR from 1600 nm to 2500 nm which has many applications such as in LIDAR, biological imaging and environmental monitoring. Using the carbon quantum dots (CQDs) in distributed feedback laser cavities, lasing with emission was tuned between 2150 nm and 2500 nm is reported. Due to the increased absorption cross-section of larger CQDs, the optical gain threshold was reduced by a […]
Specialized materials could passively control the internal temperature of space habitats
Phys.org August 19, 2024 Researchers in Spain explored the design of a space habitat thermally controlled using phase change materials (PCMs) to maintain a suitable, habitable temperature inside the habitat by isolating it from the external solar radiation. They studied the system numerically considering only diffusive heat transport scenario with practical application to microgravity or reduced gravity environments. The system dynamics were explored for a wide range of governing parameters, including the length of the PCM cell L, the thermo-optical properties at the external boundary of the habitat wall exposed to solar radiation, the eclipse fraction of the solar cycle, […]
First-ever wireless device developed to make magnetism appear in non-magnetic materials
Phys.org October 30, 2023 Magneto-ionics is a unique approach to control magnetism with electric field for low-power memory and spintronic applications. So far, magneto-ionics has been achieved through direct electrical connections to the actuated material. Researchers in Spain have shown that such control can be achieved wirelessly. Without direct wire contact inducing polarization in the conducting material immersed in the electrolyte, promoted wireless bipolar electrochemistry, an alternative pathway to achieve voltage-driven control of magnetism based on the same electrochemical processes involved in direct-contact magneto-ionics. They achieved significant tunability of magnetization for cobalt nitride thin films, including transitions between paramagnetic and […]
A new technique to detect invisibility cloaks
Phys.org June 13, 1023 So far, most efforts in invisibility science have been devoted to achieving practically realizable cloak designs and to improving the effectiveness of these devices in reducing their scattering cross-section. Little attention has been paid to the opposite side of the technology – the development of more efficient techniques for the detection of invisibility devices. Researchers in Spain proposed a path taking advantage of the smarter way in which diffraction tomography processes all overlooked information to improve the efficiency in unveiling the presence of invisibility devices. This approach not only resulted in a considerable sensitivity enhancement in […]
Storing information with light
Phys.org January 20, 2021 In the quest for energy efficient and fast memory elements, optically controlled ferroelectric memories are promising candidates. By taking advantage of the imprint electric field existing in the nanometric BaTiO3 films and their photovoltaic response at visible light, researchers in Spain have shown that the polarization of suitably written domains can be reversed under illumination. They used this effect to trigger and measure the associate change of resistance in tunnel devices. They showed that engineering the device structure by inserting an auxiliary dielectric layer, the electroresistance increases by a factor near 2 × 103%, and a robust electric […]
A new platform to stretch 2D materials
Nanowerk June 17, 2020 As the electronic and optical properties of 2D materials can be controlled by mechanical deformations of their crystal structure, strain engineering can be used to modify their electronic properties. Researchers in Spain have developed thermal strain actuators on top of polypropylene substrates to control the biaxial strain in atomically thin MoS2 layers. The actuators can reach a maximum biaxial strain of 0.64 % and reliably modulated at frequencies up to 8 Hz. The strain levels can be varied all the way from 0% to 0.6% with a negligible spatial drift. They demonstrated the operation of the […]
‘Hot and messy’ entanglement of 15 trillion atoms
Nanowerk May 15, 2020 Quantum technologies often employ strong cooling and isolation to protect entangled entities from decoherence by random interactions. Researchers in Spain heated a collection of atoms to 450 Kelvin. The individual atoms collided with each other every few microseconds, and each collision set their electrons spinning in random directions. They observed an enormous number of entangled atoms – about 100 times more than ever before observed. The entanglement is non-local and the entanglement remains for about 1 millisecond, which means that 1000 times per second a new batch of 15 trillion atoms is being entangled. This clearly […]
Researchers pave the way to designing omnidirectional invisible materials
EurekAlert May 7, 2020 Researchers in Spain have demonstrated that Maxwell’s equations, as well as the acoustic and elastic wave equations, also possess an underlying supersymmetry in the time domain. They explored the consequences of this property in the field of optics, obtaining a simple analytic relation between the scattering coefficients of numerous time-varying systems, and uncovering a wide class of reflectionless, three dimensional, all-dielectric, isotropic, omnidirectional, polarisation-independent, non-complex media. These unprecedented features may enable the creation of novel reconfigurable devices, including invisible materials, frequency shifters, isolators, and pulse-shape transformers…read more. Open Access TECHNICAL ARTICLE
Micromotors get supercharged with three ‘engines’
Nanowerk March 4, 2020 Micromotors are tiny tools that convert stimuli, such as chemical fuel, light, magnetic fields or sound, into motion to perform tasks. They are powered by one or two of these stimuli. To make a “supercharged” micromotor with three engines researchers in Spain coated polystyrene microspheres with layers of gold and 2D nanomaterials; they attached three different nanoparticles that functioned as engines making the micromotors responsive to hydrogen peroxide, magnets and light. When the micromotors were exposed to all three stimuli simultaneously, the speed increased by as much as 73% over that attained with micromotors containing only […]