The biodegradable material can help improve healing after surgery—or an avocado-related accident.
Category: materials – Page 8
Listening for quantum oscillations in the Kondo insulator ytterbium dodecaboride
Magnetic quantum oscillations have been unexpectedly observed in insulators, where freely moving charge carriers are not expected to exist. A joint study by researchers from Tokyo University of Science, The University of Tokyo and Kobe University investigated this puzzling behavior in the Kondo insulator YbB12 using ultrasound.
The findings are published in the journal Physical Review B.
While no oscillations were detected in the insulating state, clear signals emerged after the material became metallic, offering new insight into unusual quantum behavior in next-generation materials.
Scientists create optical skyrmions using a two-century-old light phenomenon
Nanyang Technological University, Singapore (NTU Singapore) scientists have used a classic optical phenomenon known as the Poisson spot to create stable patterns of light called optical skyrmions, which are tiny, swirling configurations in the properties of light—akin to the spikes of a hedgehog.
The team used a laser directed at a small circular disk instead of the complex and costly engineered materials commonly used to generate these skyrmions. This new method gives scientists a much simpler way to generate, study and adjust optical skyrmions.
Skyrmions are currently a hot scientific subject because they hold the potential to store information, paving the way for future data storage, communications and computing systems.
Broken time-reversal symmetry phase in kagome metals may establish conditions for superconductivity
Physicists have long suspected that a peculiar quantum state lurks inside a class of materials known as kagome metals, but proving its existence has been elusive. Now, a team led by Yeongkwan Kim at the Korea Advanced Institute of Science and Technology has performed experiments on a kagome metal that provide the strongest evidence yet for this exotic state.
Published in Nature Physics, the team’s results could shed new light on how these materials transition into superconductivity.
Experiment upends beliefs on how electrons actually behave in warm dense matter
Researchers at European XFEL, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Rostock University and other collaborating institutions have used high-precision experiments to demonstrate that the most widely used models for the behavior of electrons in warm dense matter are inaccurate. Warm dense matter is challenging to study, but also is of key importance for a plethora of research, including the investigation of planetary interiors, materials science and laser fusion experiments. The study is published in Physical Review Letters.
In warm dense matter, electron density oscillates. The collective oscillations are called plasmons. They carry important information and can be observed using X-rays, resulting in scattering spectra—abstract images captured by a detector. In many experiments, these spectra are interpreted using simplified uniform electron gas models. However, the new measurements show that for warm dense aluminum, these models consistently overestimate the plasmon energy by up to about 25% (about 8 electronvolts) and fail to reproduce the full measured shape of the signal.
“Our measurements are precise enough to clearly distinguish between competing models,” says Dr. Thomas Preston of European XFEL. “That is important because these models are widely used to diagnose extreme states of matter. If the model is incorrect, that leads to inaccurately inferred properties.”
Room-temperature device synchronizes distant laser spots into single coherent ‘supermode’
Researchers have demonstrated a new way to make spatially separated lasers synchronize and act as a single coherent light source—without extreme conditions or complex materials.
A team of physicists from the University of Southampton (UK), University of Warsaw (PL), Military University of Technology (PL), Institut Pascal, Université Clermont Auvergne, CNRS (FR), and CNR (IT) has developed a new class of tunable photonic devices in which multiple tiny laser beams spontaneously synchronize and behave as a unified, spatially extended and coherent light source. Remarkably, this effect is achieved at room temperature using a simple system based on liquid crystals and organic dye molecules, opening new possibilities for low-cost and reconfigurable optical technologies.
The work is published in the journal Nature Communications. The study demonstrates that spatially separated laser spots inside an optical microcavity can spontaneously phase-lock—that is, align (or synchronize) their oscillations—and form a collective state known as a “supermode.” Traditionally, such behavior has been observed only in highly specialized semiconductor systems operating at cryogenic temperatures and in the so-called strong light-matter coupling regime.
Ink-based thermoelectric technology could be solution for replacing problematic refrigerants
Today’s refrigerants, which are specialized working fluids used in air conditioners, refrigerators and heat pumps, come with a host of issues, including leakage, emissions concerns, flammability and limited reclamation of used refrigerants. However, a recent study by University of Notre Dame researchers published in Materials Horizons describes a promising alternative for next-generation cooling using thermoelectric technology, which has no moving parts and no gaseous refrigerants, allowing for zero leaks.
“By making thermoelectric devices a competitive and commercially viable technology, it can transform the way we cool things,” said Yanliang Zhang, Advanced Materials and Manufacturing Collegiate Professor of Aerospace and Mechanical Engineering at Notre Dame. “We can make the cooling process become very environmentally friendly.”
In the past, widespread adoption of thermoelectrics has been challenging because of the high costs associated with traditional manufacturing processes. However, the research team led by Zhang has developed an innovative ink-based printing strategy that enables scalable manufacturing of low-cost, high-performance thermoelectric materials and devices.
Laser ‘origami’ could help astronauts build structures on the moon
University of Florida researchers are exploring how lasers could help astronauts build structures on the moon using materials already available there, including lunar soil transformed into glass. The work, led by Victoria M. Miller, Ph.D., an associate professor in the Herbert Wertheim College of Engineering and researcher with the UF Astraeus Space Institute, recently completed a research phase focused on laser forming, a manufacturing process that bends materials without physical contact.
The team’s latest paper, published in Lasers in Manufacturing and Materials Processing, examined how different atmospheric conditions affect laser bending, an important question for future manufacturing in the vacuum of space. The long-term applications extend beyond space exploration and could also support flexible manufacturing efforts on Earth.
“It is also for Earth applications. We’re focused on flexible manufacturing for defense applications,” said Miller, who works in the Department of Materials Science and Engineering.