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Crime scene investigation may soon become significantly more accurate and efficient thanks to a new method for detecting gunshot residues. Researchers from the groups of Wim Noorduin (AMOLF/University of Amsterdam) and Arian van Asten (University of Amsterdam) developed the technique that converts lead particles found in gunshot residue into light-emitting semiconductors. This method is faster, more sensitive, and easier to use than current alternatives.

Forensic experts at the Amsterdam police force are already testing it in actual crime scene investigations. The researchers published their findings in Forensic Science International on March 9.

A pair of physicists at Universidad Nacional de Mar del Plata, in Argentina, have created a computer simulation of the famed Antikythera Mechanism and in so doing have found that manufacturing inaccuracies may have caused the device to jam so often it would have been very nearly unusable—if it was in the condition it is now. Esteban Szigety and Gustavo Arenas have posted a paper on the arXiv preprint server describing the factors that went into their simulation and what it showed.

In 1901, divers looking for sponges off the coast of the Greek island, Antikythera, discovered a among the ruins of a sunken ship. The mysterious device was dated to the late second or early first century BCE, and from that time on there has been much debate in the regarding its purpose.

Some markings on the device suggest it could be used to track time and and even predict some others, such as the arrival of a comet, courtesy of its intricate gears and pointing indicators, by turning its hand crank. Since only one of the devices has ever been found, some have suggested it had an otherworldly origin.

A research team from the Institute of Statistical Mathematics and Panasonic Holdings Corporation has developed a machine learning algorithm, ShotgunCSP, that enables fast and accurate prediction of crystal structures from material compositions. The algorithm achieved world-leading performance in crystal structure prediction benchmarks.

Crystal structure prediction seeks to identify the stable or metastable crystal structures for any given chemical compound adopted under specific conditions. Traditionally, this process relies on iterative evaluations using time-consuming first-principles calculations and solving energy minimization problems to find stable atomic configurations. This challenge has been a cornerstone of materials science since the early 20th century.

Recently, advancements in computational technology and generative AI have enabled new approaches in this field. However, for large-scale or , the exhaustive exploration of vast phase spaces demands enormous computational resources, making it an unresolved issue in materials science.

Imagine tiny LEGO pieces that automatically snap together to form a strong, flat sheet. Then, scientists add special chemical “hooks” to these sheets to attach glowing molecules called fluorophores.

Associate Professor Gary Baker, Piyuni Ishtaweera, Ph.D., and their team have created these tiny, clay-based materials—called fluorescent polyionic nanoclays. They can be customized for many uses, including advancing energy and , improving and protecting the environment.

The work is published in the journal Chemistry of Materials.

A research team at POSTECH (Pohang University of Science and Technology) has developed a new alloy that maintains its strength and ductility across extreme temperatures ranging from −196 °C to 600 °C. The findings, which have drawn attention from the aerospace and automotive industries, were published in the journal Materials Research Letters. The team was led by Professor Hyoung Seop Kim from the Department of Materials Science and Engineering, Graduate Institute of Ferrous Technology, and Department of Mechanical Engineering.

Most metals used in everyday life are sensitive to temperature changes—metal doorknobs feel icy in winter and hot in summer. Consequently, conventional metal materials are typically optimized for performance within a narrow temperature range, limiting their effectiveness in environments with dramatic temperature fluctuations.

To overcome this challenge, the POSTECH research team introduced the concept of the “Hyperadaptor” and developed a nickel-based high-entropy alloy (HEA) that embodies this idea.

A new class of semiconductors that can store information in electric fields could enable computers that run on less power, sensors with quantum precision, and the conversion of signals between electrical, optical and acoustic forms—but how they maintained two opposite electric polarizations in the same material was a mystery.

Recent studies have revealed that electrons passing through chiral molecules exhibit significant spin polarization—a phenomenon known as chirality-induced spin selectivity. This effect stems from a nontrivial coupling between electron motion and spin within chiral structures, yet quantifying it remains challenging.

To address this, researchers at the Institute for Molecular Science (IMS) /SOKENDAI investigated an organic superconductor with chiral symmetry. They focused on nonreciprocity related to and observed an exceptionally large nonreciprocal transport in the , far exceeding theoretical predictions. Remarkably, this was found in an with inherently weak spin-orbit coupling, suggesting that chirality significantly enhances charge current-spin coupling with inducing mixed spin-triplet Cooper pairs.

The work is published in the journal Physical Review Research.

Opaque materials can transmit light when excited by a high-intensity laser beam. This process, known as optical bleaching, induces a nonlinear effect that temporarily alters the properties of a material. Remarkably, when the laser is switched on and off at ultrahigh speeds, the effect can be dynamically controlled, opening new possibilities for advanced optical technologies.

Multicolored optical switching is an important phenomenon with potential applications in fields such as telecommunications and optical computing. However, most materials typically exhibit single-color optical nonlinearity under intense laser illumination, limiting their use in systems requiring multicolor or multiband switching capabilities. Currently, most optical switches are based on , which require an electric voltage or current to operate, resulting in slow response times.

To address this gap, a group of researchers, led by Professor Junjun Jia from the Faculty of Science and Engineering at Waseda University, Japan, in collaboration with Professor Hui Ye and Dr. Hossam A. Almossalami from the College of Optical Science and Engineering at Zhejiang University, China, Professor Naoomi Yamada from the Department of Applied Chemistry at Chubu University, Japan, and Dr. Takashi Yagi from the National Institute of Advanced Industrial Science and Technology, Japan, investigated the multivalley optical switching phenomenon in germanium (Ge) films.

Physicists at Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have created a compact laser that emits extremely bright, short pulses of light in a useful but difficult-to-achieve wavelength range, packing the performance of larger photonic devices onto a single chip.

Published in Nature, the research is the first demonstration of an on-chip, picosecond, mid-infrared laser pulse generator that requires no external components to operate.

The device can make what’s called an , a spectrum of light consisting of equally spaced frequency lines (like a comb), used today in precision measurements. The new laser chip could one day speed the creation of highly sensitive, broad-spectrum gas sensors for environmental monitoring, or new types of spectroscopy tools for medical imaging.