Nanowerk April 28, 2023 The continued downscaling of silicon CMOS technology presents challenges for achieving the required low power consumption. While high mobility channel materials hold promise for improved device performance at low power levels, a material system which enables both high mobility n-FETs and p-FETs, that is compatible with Si technology and can be readily integrated into existing fabrication lines is required. An international team of researchers (Germany, France, UK) has developed high performance, vertical nanowire gate-all-around FETs based on the GeSn-material system grown on Si. While the p-FET transconductance was increased to 850 µS/µm by exploiting the small band […]
Newly developed hydrogel nanocomposite for the mass production of hydrogen
Phys.org April 27, 2023 Despite recent progress in designing highly active photocatalysts, inefficient solar energy and mass transfer, the instability of catalysts and reverse reactions impede their practical large-scale applications. Storing solar energy in chemical bonds aided by heterogeneous photocatalysis is desirable for sustainable energy conversion. Researchers in South Korea designed a floatable photocatalytic platform constructed from porous elastomer–hydrogel nanocomposites. The nanocomposites at the air–water interface featured efficient light delivery, facile supply of water and instantaneous gas separation. Consequently, a high hydrogen evolution rate of 163 mmol h–1 m–2 was achieved using Pt/TiO2 cryoaerogel, even without forced convection. When fabricated in an area […]
Newly observed effect makes atoms transparent to certain frequencies of light
Phys.org April 27, 2023 Many previous experimental cavity quantum electrodynamics (cQED) studies have focused on regimes in which a small number of identical emitters interact with a weak external drive such that the system can be described with simple, effective models. However, the dynamics of a disordered, many-body quantum system subject to a strong drive have not been fully explored, despite its importance and potential in quantum applications. A team of researchers in the US (Caltech, University of Oklahoma) studying inhomogeneously broadened ensemble of solid-state emitters coupled with high cooperativity to a nanophotonic resonator under strong excitation discovered a sharp, […]
Paradoxical quantum phenomenon measured
Science Daily April 26, 2023 In the quantum world information is often closely linked to surface area. This strange and counter-intuitive fact has been theoretically predicted years ago, now it has now been measured: ‘Mutual quantum information’ scales with surface, not with volume. An international team of researchers ( Austria, Germany, France, Portugal, USA- New York University, Flatiron Institute, Switzerland) measured the von Neumann entropy of spatially extended subsystems in an ultracold atom simulator of one-dimensional quantum field theories. They experimentally verified the area law of quantum mutual information, one of the fundamental properties of equilibrium states of gapped quantum […]
Researchers call for a new approach to studying academic progress
Phys.org May 2, 2023 The scientific study of higher education has not yet matured to adequately model the complexity of the task of developing, and producing the next generation of scientists, artists, political leaders, and informed citizens. How universities structure their curriculums, and how students make progress through them, differ across fields of study, educational institutions, and nation-states. To this day, a “pipeline” metaphor shapes analyses and discourse of academic progress, especially in STEM, even though it is an inaccurate representation. A team of researchers in the US (Cornell University, University of Pennsylvania, University of Michigan, Texas A&M University, UC […]
Researchers detect and classify multiple objects without images
Science Daily May 3, 2023 Existing image-free methods still cannot simultaneously obtain the category, location, and size information of all objects. Researchers in China have reported a novel image-free single-pixel object detection (SPOD) technique which enables efficient and robust multi-object detection directly from a small number of measurements, eliminating the requirement for complicated image reconstruction. The small-size optimized pattern sampling method achieved higher image-free sensing accuracy with fewer pattern parameters than convolutional neural network (CNN). Instead of simply stacking CNN layers, they designed the SPOD network based on the transformer architecture. It can better model global features and reinforce the […]
Researchers use AI to explore potential zoonotic diseases
Phys.org April 26, 2023 When certain conditions are met, the passage of viruses from one species to another can ultimately lead to the emergence of a zoonosis. To make better predictions of interactions between mammals and viruses in general, an international team of researchers (Canada, UK, USA – University of Oklahoma, Georgetown University, Washington University) developed an algorithm to sample thousands of species of mammals and even more thousands of viruses to identify which host-virus interactions to explore further. The algorithm represents the system as a network of interactions between viruses and mammals that the algorithm must then complete. It […]
Silver nanoparticles spark key advance in thermoelectricity for power generation
Nanowerk May 1, 2023 To facilitate the development of thermoelectric modules for various operating temperature ranges, a connection technology that is suitable for heat-sensitive thermoelectric materials and capable of realizing both low-temperature connections and high-temperature service is required. Researchers at the University of Houston used low-temperature sintering of silver nanoparticles as an approach to connect the electrode and metallization layer of low- (Bi2Te3-based), medium- (PbTe-based) and high-temperature (half-Heusler-based) thermoelectric modules. Due to the low melting point of Ag nanoparticles and the high stability in the sintered bulk, the processing temperature of the module was decoupled from the operating temperature, avoiding […]
Towards a sustainable superconductor technology with magnesium diboride super magnets
Phys.org May 1, 2023 Magnesium diboride (MgB2), a binary compound, behaves as a superconductor at a moderate temperature of around 39 K (-234°C). It can replace conventional low-temperature superconductors. However, it suffers from weak magnetic flux pinning. To enhance pinning, it is essential to tune the pinning centers in MgB2—the boundaries of grains or small crystals that constitute MgB2. An international team of researchers (Japan, Czech Republic) used high-energy ultra-sonication for refining coarse B powder dispersed in 2-propanol up to nanoscale sizes. Utrasonic vibrations imparted high speeds to B particles in the solvent, leading to collisions. The resulting friction and […]
Tunneling electrons
Science Daily April 26, 2023 Researchers in Germany have shown that by superimposing two laser fields of different strengths and frequency, the electron emission of metals can be measured and controlled precisely to a few attoseconds. So far, scientists have only been able to determine laser-induced electron dynamics precisely in gases with an accuracy of a few attoseconds. Quantum dynamics and emission time windows have not yet been measured on solids. Instead of just a strong laser pulse, which emits the electrons a pointy tungsten tip, they also used a second weaker laser with twice the frequency. The electrons then […]