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Midair haptics and levitation may get steadier with predictable ultrasonic airflow

Acoustic streaming generated by airborne ultrasonic phased arrays plays a critical role in the performance of advanced ultrasonic technologies, including midair haptic feedback, odor delivery, and acoustic levitation. Researchers at University of Tsukuba have developed a predictive model for acoustic streaming in phased arrays by integrating three-dimensional acoustic and fluid simulations.

Airborne ultrasonic phased arrays focus ultrasonic waves at prescribed locations in space and dynamically steer them, enabling applications such as noncontact tactile feedback, odor transport, and the levitation of small objects.

Despite the nonnegligible influence of acoustic streaming—steady airflow induced by high-intensity sound fields—on tactile perception and the stability of levitated objects, reliable prediction and modeling of this phenomenon have remained challenging.

How did humans develop sharp vision? Lab-grown retinas show likely answer

Humans develop sharp vision during early fetal development thanks to an interplay between a vitamin A derivative and thyroid hormones in the retina, Johns Hopkins University scientists have found. The findings could upend decades of conventional understanding of how the eye grows light-sensing cells and could inform new research into treatments for macular degeneration, glaucoma, and other age-related vision disorders. Details of the study, which used lab-grown retinal tissue, are published today in Proceedings of the National Academy of Sciences.

“This is a key step toward understanding the inner workings of the center of the retina, a critical part of the eye and the first to fail in people with macular degeneration,” said Robert J. Johnston Jr., an associate professor of biology at Johns Hopkins who led the research. “By better understanding this region and developing organoids that mimic its function, we hope to one day grow and transplant these tissues to restore vision.”

A microfluidic chip for one-step detection of PFAS and other pollutants

Environmental pollutant analysis typically requires complex sample pretreatment steps such as filtration, separation, and preconcentration. When solid materials such as sand, soil, or food residues are present in water samples, analytical accuracy often decreases, and filtration can unintentionally remove trace-level target pollutants along with the solids.

To address this challenge, a joint research team led by Dr. Ju Hyeon Kim at the Korea Research Institute of Chemical Technology (KRICT), in collaboration with Professor Jae Bem You’s group at Chungnam National University, has developed a microfluidic-based analytical device that enables direct extraction and analysis of pollutants from solid-containing samples without any pretreatment. The study was published in ACS Sensors

Water, food, and environmental samples encountered in daily life may contain trace amounts of hazardous contaminants that are invisible to the naked eye.

Hologram processing method boosts 3D image depth of focus fivefold

Researchers from the University of Tartu Institute of Physics have developed a novel method for enhancing the quality of three-dimensional images by increasing the depth of focus in holograms fivefold after recording, using computational imaging techniques. The technology enables improved performance of 3D holographic microscopy under challenging imaging conditions and facilitates the study of complex biological structures.

The research results were published in the Journal of Physics: Photonics in the article “Axial resolution post-processing engineering in Fresnel incoherent correlation holography.”

One of the main limitations of conventional microscopes and 3D imaging systems is that, once an image or hologram has been recorded, its imaging properties cannot be altered. To overcome this limitation, Shivasubramanian Gopinath, a Junior Research Fellow at the University of Tartu Institute of Physics, and his colleagues have developed a new method that enables to capture a set of holograms with different focal distances at the time of acquisition, instead of a single image. These can then be computationally combined to produce a synthetic hologram that offers a much greater depth of focus than conventional approaches, and allows for post-processing of the recorded image.

Electrically controllable 3D magnetic hopfions realized in chiral magnets

A research team from the High Magnetic Field Laboratory of the Hefei Institutes of Physical Science of the Chinese Academy of Sciences, together with collaborators from Anhui University, ShanghaiTech University, and the University of New Hampshire, has demonstrated the first electrically controllable generation of hopfions—three-dimensional topological solitons—in a solid-state magnetic system. The results are published online in Nature Materials.

Proposed in 1975, hopfions are three-dimensional topological structures characterized by a Hopf charge and capable of forming rings, links, and knots. Although they are predicted to exist in a wide range of physical systems—from magnetic materials and plasmas to the early universe—their complexity has kept hopfions largely confined to theory, with only limited experimental realization and control.

In this study, the researchers used a chiral magnet as a laboratory test bed. By applying spin-transfer torque together with thermal excitation, they successfully generated magnetic hopfions in the chiral magnet FeGe.

Shaping carbon fiber with electricity: Wireless voltage pulses drive reversible bending

Controlled manipulation of fibers that are as thin as or even thinner than human hair is a real challenge. Despite technological development, the precise and reversible change of the microfibers’ orientation is not easy. The interdisciplinary team of researchers from the Institute of Physical Chemistry, Polish Academy of Sciences, has recently developed a way to control the shape of microfibers with electricity. This brings us closer to a novel technical solution in micromechanics and soft robotics.

Their recent work, published in the Nature Communications journal, demonstrates the first proof-of-concept results on the motion of pristine carbon fibers caused by asymmetric electrochemical processes occurring in the material.

X-ray platform images plasma instability for fusion energy and astrophysics

Harnessing the power of the sun holds the promise of providing future societies with energy abundance. To make this a reality, fusion researchers need to address many technological challenges. For example, fusion reactions occur within a superheated state of matter, called plasma, which can form unstable structures that reduce the efficiency of those reactions.

Characterizing different instabilities could help researchers prevent or make use of them. One particular instability, known as current filamentation, is also relevant to understanding astrophysical phenomena.

Now, for the first time, a team led by researchers at the U.S. Department of Energy’s SLAC National Accelerator Laboratory imaged how the current filamentation instability evolves in real time in high-density plasma.

Quantum research in two ways: From proving someone’s location to simulating financial markets

Quantum physics may sound abstract, but Ph.D. candidates Kirsten Kanneworff and David Dechant show that quantum research can also be very concrete. Together, they are investigating how quantum technology can change the world. While Kanneworff worked in the lab to study how quantum optics can be used to prove someone’s location, Dechant focused on quantum computing for dynamic systems, such as the financial world. The two researchers are defending their doctoral theses this week.

Imagine that you receive an email from someone posing as your bank, asking you to enter your personal details on a website. How can you verify the sender’s identity?

Kanneworff investigated a smart way to check whether someone is really in a certain place: quantum position verification. “The idea for this project came about during my master’s degree,” she says. “I found it an interesting subject. The combination of optics and quantum communication really appealed to me, especially since it has a clear application.”

IceCube upgrade adds six deep sensor strings to detect lower-energy neutrinos

Since 2010, the IceCube Observatory at the Amundsen-Scott South Pole Station has been delivering groundbreaking measurements of high-energy cosmic neutrinos. It consists of many detectors embedded in a volume of Antarctic ice measuring approximately one cubic kilometer. IceCube has now been upgraded with new optical modules to enable it to measure lower-energy neutrinos as well. Researchers at the Karlsruhe Institute of Technology (KIT) made a significant contribution to this expansion.

IceCube serves to measure high-energy neutrinos in an ice volume of one cubic kilometer. As neutrinos themselves do not emit any signals, the tracks of muons and other secondary particles are measured precisely. Muons are elementary particles sometimes produced by the interaction of neutrinos with ice. Contrary to neutrinos, muons carry an electric charge. On their way through the ice, they produce a characteristic light cone, which is detected by highly sensitive detectors.

Now, 51 researchers from around the world have installed six new strings of novel sensors up to 2,400 meters deep into the eternal ice, thereby expanding the IceCube experiment to also measure low-energy neutrinos.

A New Way To Cool Quantum Computers Could Change How They’re Built

By using controlled microwave noise, researchers created a quantum refrigerator capable of operating as a cooler, heat engine, or amplifier. This approach offers a new way to manage heat directly inside quantum circuits. Quantum technology has the potential to reshape many core areas of society.

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