Lifeboat Foundation

Graphene is the setting for the first demonstration of relativistic electrons’ paradoxical ability to whiz through a barrier, provided the barrier is high enough.

If an electron in a material has a speed that is independent of its energy and if it encounters a barrier head on, it can tunnel straight through. Derived by theorist Oskar Klein in 1929, this counterintuitive finding remained little tested in the lab because it is hard to make electrons approach a barrier head on and to stop them scattering off the edges of the sample. Now Mirza Elahi of the University of Virginia and his collaborators have observed evidence of Klein tunneling in monolayer graphene. What’s more, they also observed the opposite effect, anti-Klein tunneling, in bilayer graphene. In anti-Klein tunneling, head-on electrons do not tunnel at all, while others approaching the barrier at an intermediate angle do [1].

Graphene’s hexagonal lattice can be thought of as two identical interpenetrating triangular sublattices. One consequence of that view is that graphene’s charge carriers—electrons that hop between the two sublattices—behave as if massless and relativistic at low energies. Another consequence is that the two sublattices bestow on the electrons a chiral property, pseudospin, that resembles spin, which controls the nature of the transmission across the barrier.

The performance of numerous cutting-edge technologies, from lithium-ion batteries to the next wave of superconductors, hinges on a physical characteristic called intercalation. Predicting which intercalated materials will be stable poses a significant challenge, leading to extensive trial-and-error experimentation in the development of new products.

Now, in a study recently published in ACS Physical Chemistry Au, researchers from the Institute of Industrial Science, The University of Tokyo, and collaborating partners have devised a straightforward equation that correctly predicts the stability of intercalated materials. The systematic design guidelines enabled by this work will speed up the development of upcoming high-performance electronics and energy-storage devices.

The Southwest Research Institute (SwRI) is developing a spacecraft named Astroscale Prototype Servicer for Refueling (APS-R) as part of a $25.5 million project with the U.S. Space Force.

Southwest Research Institute (SwRI) will build, integrate, and test a small demonstration spacecraft as part of a $25.5 million Space Mobility and Logistics (SML) prototyping project funded by the U.S. Space Force and led by prime contractor Astroscale U.S. The spacecraft, called the Astroscale Prototype Servicer for Refueling (APS-R), will refuel other compatible vehicles while in geostationary orbit.

“Running low on fuel is a common issue for spacecraft in Earth orbit,” said SwRI Staff Engineer Steve Thompson, the SwRI project systems engineer. “When they have expended all of their fuel, their mission ends — even though the vehicle may be in otherwise excellent health. A refueling vehicle can extend those missions, and we can get additional lifetime out of spacecraft that are already in orbit.”

For the first time, scientists have built a fusion experiment using permanent magnets, a technique that could show a simple way to build future devices for less cost and allow researchers to test new concepts for future fusion power plants.

Researchers at Fudan University in China have recently been trying to identify new promising quantum anomalous Hall insulators. Their latest paper, published in Physical Review Letters, outlines the unique characteristics of monolayer V₂MX₄, which could belong to a new family of quantum anomalous Hall insulators.

“Finding intrinsic quantum anomalous Hall materials is an important goal in topological material research,” Jing Wang, co-author of the paper, told Phys.org. “After we predicted MnBi₂Te₄, a paradigm example of magnetic topological insulator and exhibiting quantum anomalous Hall effect in odd layer, we have been thinking about finding new intrinsic quantum anomalous Hall insulator with large gap.”

Large-gap quantum anomalous Hall insulator materials exhibit a quantum anomalous Hall effect with a relatively large energy gap between the valence and conduction band. These materials should exhibit a synergy between two seemingly conflicting properties, namely spin-orbit coupling and ferromagnetism.

In an era where the quest for sustainable energy sources has become paramount, researchers are tirelessly exploring innovative avenues to enhance fuel production processes. One of the most important tools in converting chemical energy into electrical energy and vice versa is electrocatalysis, which is already used in various green-energy technologies.

Two scientists at the Swiss Laboratory of Nanoscience for Energy Technologies in the School of Engineering may have hit upon a way to simultaneously produce clean water and clean electricity, all with zero pollution.

Giulia Tagliabue, the head of the laboratory, and Tarique Anwar, a PhD student, focused their research on hydrovoltaic effects, which can harness the power of evaporation to provide a continuous flow of energy in order to harvest electricity using specialized nanodevices.

Continue reading “Scientists make ‘major finding’ with nanodevices that can seemingly produce energy out of thin air: ‘Contradicting prior understanding’” »

As many as three billion tonnes of methane is released from hydroelectric power plants that could be repurposed as fuel if captured.

As AFP reports, in a meeting with industry experts, an economy ministry official outlined a target completion date of post-2035. To achieve this ambitious goal, a significant investment of five trillion yen ($33 billion) will be allocated over the next decade, fueling research and development of the new passenger plane.

This latest endeavor seeks to establish Japan as a leader in passenger aircraft production – a position it hasn’t held in over half a century. Building on the challenges that Mitsubishi Heavy Industries (MHI) encountered, which canceled its long-delayed passenger jet project in 2023, the new public-private consortium strongly emphasizes clean energy.