Science Daily August 26, 2021 Although tens of unconventional superconductors have been discovered in the past half century, there was good thermodynamic evidence of more than one superconducting phase in only one or two materials. An international team of researchers (Germany, New Zealand, UK) used thermodynamic probes to establish two-phase superconductivity in CeRh2As2. Both materials have the highest critical magnetic field to superconducting transition temperature ratio of any known superconductor. The findings can be expected to generate entirely new research directions…read more. TECHNICAL ARTICLE
Category Archives: Advanced materials
Dual-phase alloy extremely resistant to fractures
Phys.org August 20, 2021 An international team of researchers (China, USA – Argonne National Laboratory, University of Tennessee, Germany) has developed a new type of multi-principal element alloys (MPEA) called DS: EHEA (Directly Solidified: Eutectic High-Entropy Alloy) that features multiscale spatial heterogeneities using eutectic high-entropy alloys. They found that a particular aluminum-iron-cobalt-nickel dual-phase alloy solidified in a herringbone micropattern that was very highly resistant to fracturing. Its secret, they discovered, was in its hard and soft phases and the way cracks formed. Those that formed during the hard phase were stopped when they reached a border with a soft phase—the […]
New insulation material provides more efficient electricity distribution
Phys.org August 26, 2021 One way to reduce transmission loses such as this is by increasing the direct current voltage level. However, an increase in the transmission voltage adversely affects the insulation of an HVDC cable. An international team of researchers (Sweden, Italy) have shown that by adding very small amounts of the conjugated poly(3-hexylthiophene) (P3HT), it is possible to lower the electrical conductivity by up to three times. The work opens new possibilities for manufacturers. The researchers believe that their discovery could lead to numerous new applications and directions for research…read more. Open Access TECHNICAL ARTICLE
Woven nanotube fibers turn heat into power
Phys.org August 16, 2021 Invisibly small carbon nanotubes aligned as fibers and sewn into fabrics become a thermoelectric generator that can turn heat from the sun or other sources into energy. An international team of researchers (USA – Rice University, Japan) made custom nanotube fibers and test their potential for large-scale applications. They fabricated a textile thermoelectric generator based on these carbon nanotube fibers, which demonstrated high thermoelectric performance, weavability, and scalability. The power factor they observed make these fibers strong candidates for the emerging field of thermoelectric active cooling, which requires a large thermoelectric power factor and a large […]
New evidence of an anomalous phase of matter brings energy-efficient technologies closer
Phys.org July 14, 2021 An international team of researchers (UK, Japan, Slovenia, India, USA – Columbia University, Switzerland) used ultrafast pump-probe microscopy to investigate the possible excitonic insulator Ta2NiSe5. Below 328 K, they observed the anomalous micrometer-scale propagation of coherent modes at velocities of ~105 m/s, which they attributed to the hybridization between phonon modes and the phase mode of the condensate. They developed a theoretical framework to support this explanation and proposed that electronic interactions provide a substantial contribution to the ordered phase in Ta2NiSe5. These results allow us to understand how the condensate’s collective modes transport energy and […]
New type of metasurface allows unprecedented laser control
Phys.org June 29, 2021 An international team of researchers (USA – Harvard University, Italy) has developed a tunable laser that has two components—a laser diode and a reflective metasurface. The metasurface surface uses supercells, groups of pillars which work together to control different aspects of light. It is designed so that only the selected wavelength has the correct direction to enter back in the diode enabling the laser to operate only at that specific wavelength. The wavelength can be changed by moving the metasurface with respect to the laser diode. The shape of the laser beam can be fully controlled […]
Unlocking radiation-free quantum technology with graphene
Nanowerk July 8, 2021 Making usable quantum technologies out of rare-earth compounds has remained a challenge because they contain critically radioactive compounds rendering them of limited use in real-world quantum technologies. An international team of researchers (Switzerland, Finland) used the sub-nanometre thickness of graphene to create heavy fermions. By layering thin sheets of carbon on top of one another in a specific pattern, where each sheet is rotated in relation to the other, it is possible to create the quantum properties effect that results in the electrons in the graphene behaving like heavy fermions. While in this work they showed the […]
Growing ‘metallic wood’ to new heights
Phys.org June 29, 2021 Nanolattices exhibit attractive mechanical, energy conversion and optical properties, but it is challenging to fabricate large nanolattices while maintaining the dense regular nanometre features that enable their properties. Researchers at the University of Pennsylvania developed a crack-free self-assembly approach for fabricating centimetre-scale nickel nanolattices with much larger crack-free areas. The nanolattices have a feature size of 100 nm, a grain size of 30 nm and a tensile strength of 260 MPa, which approaches the theoretical strength limit for porous nickel. The work may advance the fabrication and applications of high-strength multifunctional porous materials…read more. TECHNICAL ARTICLE
Scientists design 3D-grown material that could speed up production of new technologies for smart buildings and robotics
Phys.org June 29, 2021 An international team of researchers (UC Berkeley, Lawrence Berkeley National Laboratory, UK) has developed a nanoparticle composite that grows into 3-D crystals. They discovered that a tiny trace of polyolefin molecules from the centrifuge tube lining had somehow entered the mix. Subsequent experiments revealed that as the toluene solvent quickly evaporates at room temperature, the polyolefin additive helps the Au-PS nanoparticles form into 3D PGNP crystals, and to grow into crystal structure and the size and shape of the 3D PGNP crystals are driven by the kinetic energy of olyolefins as they precipitate in the solution. […]
Meringue-like material could make aircraft as quiet as a hairdryer
Pys.org June 18, 2021 Researchers in the UK have developed an ultralight graphene oxide (GO)/polyvinyl alcohol (PVA) aerogel (GPA) with hierarchical and tunable porosity embedded in a honeycomb scaffold. The aerogels have an enhanced ability to dissipate sound energy, with an extremely low density of 2.10 kg m−3. They experimentally evaluated and optimised the effects of composition and thickness on sound absorption, and sound transmission losses. Then employed a semi-analytical approach to evaluate the effect of different processing times on acoustic properties and assessed the relationships between the acoustic and non-acoustic properties of the materials. Over the 400–2500 Hz range, […]