Phys.org February 25, 2020 An international team of researchers (China, USA – University of Tennessee, Israel) reported the experimental evidence for the unconventional superconductivity generated by the surface states in TaIrTe4 from both scanning tunneling microscopy/ spectroscopy (STM/STS) and electrical transport measurements. They demonstrated its superconductivity by both the superconducting gap from STS and the consistent resistance drop from electrical transport. The thickness-independence of ultralow critical current and angular dependence of upper critical field (Bc2) indicate that the superconductivity occurs only in the surface states. The research offers a novel platform for exploring topological superconductors and may contribute to the […]
Tag Archives: Advanced materials
Shining a new light on biomimetic materials
Phys.org February 25, 2020 Self-trapped light beams hold potential for optical interconnects, applications in image transmission, rerouting light, logic gates for computing and for the next-generation light-guiding-light signal processing. However, self-trapping suffers from either the need for large incident beam power and loss of beam interactions at large distances, or it is slow and irreversible. An international team of researchers (Canada, USA – Harvard University, University of Pittsburgh) has shown that rapidly and repeatably switchable self-trapped laser beams with remote communication capabilities can be elicited at exceptionally small intensities in a pliant, processable hydrogel functionalized with a chromophore. According to […]
Synthesizing a superatom: Opening doors to their use as substitutes for elemental atoms
Science Daily February 25, 2020 Scientists have shown particular interest in superatomic structures, since they can be linked with atoms to produce molecules, and potentially be used to substitute certain elements in many applications. But for superatoms to be effectively utilized, they must be specially tailored to resemble the characteristics of the corresponding elements. Researchers in Japan fabricated clusters of the element gallium in solution to demonstrate the effects of changing the number of atoms in a cluster on the properties of the cluster. The team synthesized Ga clusters of 3, 12, 13 using a specialized superatom synthesizer. The 13-atom […]
Van der Waals magnets, a material for future semiconductors
Nanowerk February 16, 2020 When van der Waals materials are combined with other 2D materials, they can create new materials that show previously undiscovered properties. However, most van der Waals magnetic materials have some constraints in terms of spintronics application because of their low Curie temperature and high coercivity making them unsuitable for use in certain devices. An international team of researchers (South Korea, USA – Brookhaven National Laboratory, Lawrence Berkeley National Laboratory) found that Fe3–xGeTe2 nanoflakes show a significant suppression of the magnetic anisotropy with hole doping. Electronic structure measurements and calculations revealed that the chemical potential shift associated […]
Researchers develop smaller, lighter radiation shielding
Science Daily February 12, 2020 Commonly used shielding in aerospace devices consists of putting an aluminum box around any sensitive technologies has been viewed as providing the best tradeoff between a shield’s weight and the protection it provides. A team of researchers in the US (industry, North Carolina State University) has developed a technique that relies on mixing oxidized metal powder — rust — in a polymer, and then incorporating it into a common conformal coating on the relevant electronics. Radiation transport calculations show that inclusion of the metal oxide powder provides shielding comparable to a conventional shield, at low […]
Closely spaced hydrogen atoms could facilitate superconductivity in ambient conditions
Phys.org February 3, 2020 An international team of researchers (Switzerland, USA – University of Illinois, Oak Ridge National Laboratory, Poland) conducted neutron scattering experiments on zirconium vanadium hydride at atmospheric pressure and at temperatures from -450 degrees Fahrenheit to as high as -10 degrees Fahrenheit and observed hydrogen-hydrogen atomic distances in the metal hydride, as small as 1.6 angstroms, compared to the 2.1 angstrom distances predicted for these metals. Computer simulations of the data proved conclusively that the unexpected spectral intensity occurs only when distances between hydrogen atoms are closer than 2.0 angstroms. The findings could possibly facilitate superconductivity at […]
New encapsulation technique protects electronic properties of sensitive materials
Science Daily January 29, 2020 Indium selenide and gallium selenide are emerging two-dimensional semiconductors with appealing electronic properties. However, they are sensitive to air and device fabrication processes which induce structural damage and hamper their intrinsic properties. An international team of researchers (USA -Columbia University, Germany, Japan) has demonstrated an encapsulating technique where two layers of hBNhexagonal boron nitride (hBN) entirely covers the 2D layers of InSe and GaSe passivating them from the environment and isolating them from the charge disorder at the SiO2 surface. They demonstrated a strong and reproducible photo response and long-term stability. The technique can open […]
Scientists create thin films with tantalizing electronic properties
Science Daily December 23, 2019 An international team of researchers (USA – SUNY New York, Los Alamos National Laboratory, Rensselaer Polytechnic Institute, China) has fabricated barium zirconium sulfide (BaZrS3) thin films by sulfurization of oxide films deposited by pulsed laser deposition. They showed that these films are n-type with carrier densities in the range of 1019-1020 cm−3. Temperature dependent conductivity measurements suggest shallow donor levels. By assuring that BaZrS3 is a promising candidate, these results potentially unleash a family of chalcogenide perovskites for optoelectronics such as photodetectors, photovoltaics, and light emitting diodes…read more. TECHNICAL ARTICLE
New method to remove dust on solar panels
Science Daily December 9, 2019 To better understand the forces that attach and detach particles from surfaces during the self-cleaning mechanism and the effect of nanotextures on these forces, researchers in Israel prepared four silicon-based samples relevant to solar panels: (1) smooth hydrophilic (2) nanotextured hydrophilic surfaces and (3) smooth hydrophobic (4) nanotextured hydrophobic surfaces. They found that hydrophilic particle removal increased from ∼41%, from hydrophilic smooth Si wafers to 98% from superhydrophobic Si-based nanotextured surfaces. They determined that the reason for the increased particle removal is due to the reduction of the adhesion force between the particle and the […]
Study sheds light on the peculiar ‘normal’ phase of high-temperature superconductors
Science Daily December 3, 2019 In the cuprate high-temperature superconductors, the metallic state above the highest transition temperature is anomalous and is known as the “strange metal.” An international team of researchers (USA – Stanford University, SLAC National Accelerator Laboratory, UC Berkeley, the Netherlands, Japan) studied this state using angle-resolved photoemission spectroscopy. With increasing doping across a temperature-independent critical value pc ~ 0.19, they observed that near the Brillouin zone boundary, the strange metal, characterized by an incoherent spectral function, abruptly reconstructs into a more conventional metal with quasiparticles. Above the temperature of superconducting fluctuations, the pseudo gap also discontinuously […]