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Pressure turns Ångström-thin semiconducting bismuth into a metal, expanding options for reconfigurable electronics

Two-dimensional (2D) materials, sparked by the isolation of Nobel-prize-winning graphene in 2004, has revolutionized modern materials science by showing that electrical, optical, and mechanical behaviors can be tuned simply by adjusting the thickness, strain, or stacking order of such 2D materials. From transistors and flexible display to neuromorphic chips, the future of electronics is expected to be significantly empowered by 2D materials.

In a new study published in Nano Letters titled “Pressure-Driven Metallicity in Ångström-Thickness 2D Bismuth and Layer-Selective Ohmic Contact to MoS2,” researchers led by SUTD have discovered that a gentle squeeze is enough to make bismuth—one of the heaviest elements in the periodic table—switch its electrical personality.

Using state-of-the-art density functional theory (DFT) simulations, the team showed that when a single layer of bismuth, only a few atoms thick, is compressed or “squeezed” between surrounding materials, the atoms reorganize from a slightly corrugated (or buckled) structure into a perfectly flat one. This structural flattening, though subtle, has dramatic electronic consequences: it eliminates the energy band gap and allows electrons to move freely, turning the material metallic.

Amazon: This week’s AWS outage caused by major DNS failure

Amazon says a major DNS failure was behind a massive AWS (Amazon Web Services) outage that took down many websites and online services on Monday.

As BleepinComputer reported earlier this week, this incident impacted a critical Northern Virginia data center in the US-EAST-1 region, affecting users worldwide, including the United States and Europe, for over 14 hours.

According to a post-mortem published on Thursday, a race condition caused a major DNS failure in Amazon DynamoDB’s infrastructure, specifically within its DNS management system that controls how user requests are routed to healthy servers, which led to the accidental deletion of all IP addresses for the database service’s regional endpoint.

Uncertainty-aware Fourier ptychography enhances imaging stability in real-world conditions

Professor Edmund Lam, Dr. Ni Chen and their research team from the Department of Electrical and Electronic Engineering under the Faculty of Engineering at the University of Hong Kong (HKU) have developed a novel uncertainty-aware Fourier ptychography (UA-FP) technology that significantly enhances imaging system stability in complex real-world environments. The research has been published in Light: Science & Applications.

Fourier ptychography, widely regarded as a cornerstone of computational imaging, enables wide field-of-view and high-resolution imaging with broad applications ranging from microscopy to X-ray and remote sensing. However, its practical implementation has long been hindered by misalignments, , and poor data quality—challenges common across computational imaging fields.

The team’s UA-FP framework innovatively incorporates uncertainty parameters into a fully differentiable computational model, enabling simultaneous system uncertainty quantification and correction and significant enhancement of imaging performance—even under suboptimal or interference-prone conditions. This advancement represents not only an advance in ptychography but also a transformative development for computational imaging as a whole.

Metal organic frameworks enable a key step toward greener lighting and display technologies

Scientists at Oregon State University have taken a big step toward lighting and display technologies that are more energy efficient and better for the planet. The work centers around crystalline, porous materials known as metal organic frameworks, often abbreviated as MOFs, and points toward next-generation materials that may end reliance on rare earth metals.

The study by Kyriakos Stylianou, associate professor of chemistry in the OSU College of Science, and graduate students Kyle Smith and Ankit Yadav appears in Nature Communications.

The findings are important because displays—ubiquitous in communications, computing, medical monitoring and many other aspects of everyday life—and lighting contribute heavily to global energy consumption and . The that underpin those technologies—europium, terbium, yttrium, cerium, gadolinium and others—are expensive and environmentally hazardous to mine and process.

Scientists discover way to pause ultrafast melting in silicon using precisely timed laser pulses

A team of physicists has discovered a method to temporarily halt the ultrafast melting of silicon using a carefully timed sequence of laser pulses. This finding opens new possibilities for controlling material behavior under extreme conditions and could improve the accuracy of experiments that study how energy moves through solids.

The research, published in the journal Communications Physics, was led by Tobias Zier and David A. Strubbe of the University of California, Merced, in collaboration with Eeuwe S. Zijlstra and Martin E. Garcia from the University of Kassel in Germany. Their work focuses on how intense, affect the atomic structure of silicon—a material widely used in electronics and solar cells.

Using , the researchers showed that a single, high-energy laser pulse typically causes silicon to melt in a fraction of a trillionth of a second.

Scientists capture real-time melting of 2D skyrmion lattices using magnetic fields

What occurs during the melting process in two-dimensional systems at the microscopic level? Researchers at Johannes Gutenberg University Mainz (JGU) have explored this phenomenon in thin magnetic layers.

“By utilizing skyrmions, i.e., miniature magnetic vortices, we were able to directly observe, for the first time, the transition of a two-dimensional ordered structure into a disordered state at the in real time,” explained Raphael Gruber, who conducted the research within the working group of Professor Mathias Kläui at the JGU Institute of Physics.

The findings, published in Nature Nanotechnology, are fundamental to a deeper understanding of melting processes in two dimensions and the behavior of skyrmions, which may revolutionize future data storage technologies.

Common crystal proves ideal for low-temperature light technology

Superconductivity and quantum computing are two fields that have seeped from theoretical circles into popular consciousness. The 2025 Nobel Prize in physics was awarded for work in superconducting quantum circuits that could drive ultra-powerful computers. But what may be less well known is that these promising technologies are often possible only at cryogenic temperatures—near absolute zero. Unfortunately, few materials can handle such extremes. Their cherished physical properties disappear when the chill is on.

In a new paper published in Science, however, a team of engineers at Stanford University spotlights a promising material—strontium titanate, or STO for short—where the optical and mechanical characteristics do not decline at extreme low temperatures, but actually get significantly better, outperforming existing materials by a wide margin.

They believe these findings suggest that STO could become the building block for new light-based and mechanical cryogenic devices that push , , and other fields to the next level.

Microscopic ‘ocean’ on a chip reveals new nonlinear wave behavior

University of Queensland researchers have created a microscopic “ocean” on a silicon chip to miniaturize the study of wave dynamics. The device, made at UQ’s School of Mathematics and Physics, uses a layer of superfluid helium only a few millionths of a millimeter thick on a chip smaller than a grain of rice.

The work is published in the journal Science.

Dr. Christopher Baker said it was the world’s smallest wave tank, with the quantum properties of superfluid helium allowing it to flow without resistance, unlike classical fluids such as water, which become immobilized by viscosity at such small scales.

Novel carbon nanotube-based transistors reach THz frequencies

Carbon nanotubes (CNTs), cylindrical nanostructures made of carbon atoms arranged in a hexagonal lattice, have proved to be promising for the fabrication of various electronic devices. In fact, these structures exhibit outstanding electrical conductivity and mechanical strength, both of which are highly favorable for the development of transistors (i.e., the devices that control the flow of current in electronics).

In recent years, several have started using CNTs to develop various electronics, including metal-oxide-semiconductor field-effect transistors (MOSFETs). MOSFETs are transistors that control the flow of current through a semiconducting channel utilizing an applied to a gate electrode.

Notably, when arrays of CNTs are used to develop MOSFETs, they can operate at (RF), the range of electromagnetic waves that support wireless communication. The resulting MOSFETs could thus be particularly advantageous for the advancement of wireless communication systems and technologies.

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