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Metal hydride molecule trapped with laser light opens path to ultracold hydrogen

Controlling and trapping molecules, units of a substance consisting of two or more chemically bound atoms, with laser light is significantly more challenging than trapping individual atoms. This is because molecules exhibit more complex vibrational and rotational dynamics that make them more difficult to cool and trap.

In a paper published in Physical Review Letters, researchers at Columbia University and Indiana University Bloomington reported the effective cooling and trapping of calcium monohydride (CaH), a molecule consisting of a calcium atom and a hydrogen atom bound together.

This was achieved using a three-dimensional (3D) magneto-optical trap (MOT), a device that uses carefully arranged laser beams and magnetic fields to cool and confine particles.

Dog-bone design helps 2D nanoribbon transistors stay fast and efficient as widths shrink

Transistors, small semiconductor-based switches that control the flow of electricity, are central components of all electronic devices, from computers to smartphones, wearables, sensors and smart appliances. Over the past decades, electronics engineers have been continuously working to boost the speed and performance of transistors while also reducing their size.

A promising approach for miniaturizing transistors entails the use of two-dimensional (2D) semiconductors, materials that are only one or a few atoms thick. Despite their potential, most high-performing 2D transistors have so far been demonstrated using relatively wide channels, and it has remained unclear whether their performance can be preserved when the channels are made much narrower.

Researchers at Stanford University recently developed new compact transistors based on narrow strips of monolayer 2D semiconducting materials known as nanoribbons. These transistors, introduced in a paper published in Nature Nanotechnology, were found to perform remarkably well despite their small size, outperforming previously developed nanoribbon transistors based on the same 2D materials.

Ultraluminous X-ray source in Whale galaxy investigated for spectral and timing variability

Astronomers from Germany and Turkey have analyzed available data from various space telescopes to investigate an ultraluminous X-ray source designated X-4, which is located in the nearby galaxy NGC 4631. Results of the new study, published June 22 on the preprint server arXiv, yield important insights into the spectral and timing variability of this source.

Ultraluminous X-ray sources (ULXs) are point sources in the sky that are so bright in X-rays that each emits more radiation than a million suns emit at all wavelengths. They are less luminous than active galactic nuclei but more consistently luminous than any known stellar process. Although numerous studies of ULXs have been conducted, the basic nature of these sources remains unknown.

Glass cells of atoms offer a new path to smarter, cheaper sensors

More accurate navigation systems and improved wireless communications may not come from traditional electronics, but rather from atoms. Researchers at Penn State and the National Institute of Standards and Technology (NIST) have developed a new way to build tinier, smarter glass sensors filled with highly precise and stable atoms.

The team’s work, published this week (June 18) in Microsystems and Nanoengineering, centers on a manufacturable, silicon-free version of traditional bulky “vapor cells”—sealed chambers that contain cesium and rubidium atoms—that are commonly used in precision measurement systems, in a gas state. These atoms can act as highly precise sensors because, unlike manufactured components, atoms are fundamentally identical.

“Using atoms for sensing is advantageous because the physics of individual atoms is very well understood, and all the atoms are equal,” said Daniel Lopez, co-lead author of the paper, Liang Professor of Electrical Engineering and Computer Science at Penn State and director of the Nanofabrication Lab at the Materials Research Institute (MRI). “That gives you a level of precision that’s very hard to achieve with traditional microfabricated devices.”

Clean crystal surface lets single molecules hit ultimate quantum limit

Scientists at the Max Planck Institute for the Science of Light (MPL) have developed a technique for interrogating molecules on surfaces with spectroscopic precision, thereby reaching the ultimate quantum limit for the first time. With their findings, published in Science, the researchers open new opportunities for the study of molecule-surface interactions and molecular quantum technologies.

Many optical quantum technologies rely on nanoscale objects, such as atoms or molecules, that interact strongly with light. These quantum emitters are used for generating single photons, storing quantum information and entanglement distribution, processes that find application in quantum communication and computation.

To investigate these emitters individually, researchers need to keep them in one place for a long time. This is usually achieved by either trapping them in a vacuum or placing them inside a bulk material. Quantum emitters located on a surface would create new opportunities to manipulate their functionalities by “touching them,” for example, with an atomically sharp tip, as is used in scanning tunneling microscopy (STM) and atomic force microscopy (AFM).

Semiconductor quantum dots ‘reawaken’ predicted Rabi oscillations, boosting quantum control

Physicists at Paderborn University have, for the first time, experimentally demonstrated the so-called “return” of Rabi oscillations in semiconductor quantum dots. The phenomenon, which was first predicted theoretically in 2007, describes the decrease in the emission intensity of the quantum dots, which are initially damped by interactions with the lattice vibrations of a solid (phonons).

Only through sufficiently strong optical excitation can the original intensity be restored and the oscillation “reawakened”—an effect that previously existed only in idealized theoretical models and has now been proven.

The results, published in Physical Review Letters, mark a decisive step toward scalable quantum applications.

Novel crystal strategy delivers near-perfect zero thermal expansion from 11 K to 893 K

Almost every material expands when heated. Well-known examples include railroad tracks and concrete roadways, which feature visible expansion gaps to accommodate this effect. However, thermal expansion poses a far more acute challenge for extremely precise technologies, such as lasers and semiconductor manufacturing equipment, where even minute dimensional changes can compromise precision.

Scientists have long sought to develop materials that maintain dimensional stability across a wide temperature range.

Now, a team led by Prof. Lin Zheshuai from the Technical Institute of Physics and Chemistry (TIPC) of the Chinese Academy of Sciences (CAS) has designed a material with an exceptionally broad zero-thermal-expansion temperature window.

Europe’s First TES Spectrometer Makes Previously Impossible X-Ray Experiments Possible

Europe’s first TES spectrometer is transforming X-ray research with up to 1,000 times greater sensitivity, making once impossible experiments finally possible. Europe’s first and only TES spectrometer at a synchrotron light source is now operating at BESSY II, marking a major advance for X-ray re

This Sodium Battery From China Matched Tesla in a Surprising Head-to-Head Test

A new study found that a commercial sodium-ion battery from China rivals Tesla’s batteries in manufacturing quality and several key performance benchmarks.

With improvements to cold-weather charging and energy density, sodium-ion batteries could become a more affordable alternative for electric vehicles and grid-scale energy storage.

Sodium-ion battery shows tesla-like quality in new study.

Miasma Malware Targets npm Packages and GitHub Actions in Supply Chain Attack

Cybersecurity researchers have flagged yet another evolution of the supply chain attack linked to the Mini Shai-Hulud, Miasma, and Hades malware family that has compromised a new set of npm packages, even as it has propagated to the Go ecosystem.

“The latest activity includes malicious npm releases affecting LeoPlatform and RStreams packages, GitHub Actions workflow abuse, and a related Go module compromise involving the Verana Blockchain project,” Socket said.

The end goal of the campaign, as before, is to harvest developer or maintainer credentials and weaponize the stolen data to spread across package registries, repositories, and trusted developer workflows.

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