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Quantum sensor loop design could improve magnetic measurements for medicine and communications

Adelaide University quantum engineers have found a new way to improve some of the world’s most sensitive sensors of electromagnetic fields, a breakthrough that could help advance brain imaging, medical diagnostics, communications technology and next-generation quantum devices.

The research, published today in Physical Review Applied, is led by the university’s Quantum and Nano Technology Group (QuaNTeG) and solves a long-standing problem that has limited the performance of superconducting quantum interference devices, known as SQUIDs.

SQUIDs are among the most sensitive magnetic field detectors ever created. They are used in specialized applications including brain imaging systems, scientific instruments and advanced radio-frequency sensors. However, while they can detect incredibly small changes in magnetic fields, they have struggled to accurately identify when a magnetic field is exactly zero.

Against all expectations, researchers control the magnetic core of a single atom

Researchers at Delft University of Technology (the Netherlands) have succeeded in controlling the magnetism in the nucleus of a single atom with radio waves. This came as a surprise: until now, physicists believed that this nuclear spin could not be manipulated directly. The discovery could open up new possibilities for storing and reading quantum information. The research is published in the journal Nature Communications.

In metals such as iron and nickel, every atom is slightly magnetic. But inside the atom, different magnetic “compass needles,” known in quantum mechanics as spins, are also at work. “By far the strongest magnetism comes from the electrons,” says lead researcher Sander Otte. “But in some atoms, the nucleus also carries a spin. That spin is much weaker, but it is also much better shielded from the outside world.”

Otte’s group studies spins using a converted scanning tunneling microscope. This enables electrical signals to be directed with extreme precision at a single atom. In the past, the researchers mainly focused on the electron spin, which is the easiest to read out. The nuclear spin appeared only indirectly, through the so-called hyperfine interaction. This causes the spins of the nucleus and the electron to become slightly entangled.

Can gravitational fields break and reconnect? Einstein’s equations suggest they can

More than a century after Einstein first devised the equations that describe gravity, physicists are still finding new ways of interpreting them. Luca Comisso, an associate research scientist in Columbia University’s departments of Astronomy and Physics and the Columbia Astrophysics Laboratory, and Felipe A. Asenjo of Universidad Adolfo Ibáñez in Chile, recently found a new way of looking at Einstein’s equations that reveals a striking analogy with “magnetic reconnection” in plasmas, which occurs when magnetic field lines break and reconnect, powering explosive phenomena such as solar flares.

Their work shows that something similar can happen to gravity: Under the right conditions, gravitational field structures can also break and reconnect—a process they call “gravitational reconnection.” When they do, energy moves out of the gravitational field and into matter.

The findings, published in Physical Review D, could help physicists better understand some of the universe’s most extreme events, including the collision of black holes. In these environments, gravity is so powerful that space-time becomes highly distorted, making its behavior extraordinarily difficult to calculate. The researchers’ approach offers a way to identify fundamental rules governing how gravitational fields behave, potentially revealing insights that conventional computer simulations alone cannot provide.

Sound-levitated particles reveal how static charge builds up

When two objects touch and then separate, they can swap tiny amounts of electric charge, even if they are made from exactly the same material. This ‘triboelectric effect’ is the source of everyday static electricity, but it is still poorly understood in large samples of powder, where vast numbers of particles are constantly colliding with each other.

Through new research published in Physical Review E, Tom O’Hara and colleagues at the University of Bristol have investigated the effect using acoustic levitation: using sound waves to trigger repeated collisions between pairs of particles. Their experiment shows for the first time how charge builds up on repeatedly colliding particles, before leveling off at a set limit.

Could next-gen artificial intelligence help map out future space outposts?

Planning a successful trip can be challenging, especially when your destination is in outer space. Even before liftoff, space missions require extraordinary amounts of scientific preparation and data analysis to succeed, which can take years to complete. However, as space agencies race to establish a permanent presence on the moon, using artificial intelligence to combine such information into a single system could make mission planning much more efficient.

One such system, developed by Gokce Inal, a Ph.D. candidate in civil, environmental and geodetic engineering at The Ohio State University, is an AI framework designed to help scientists evaluate potential lunar landing sites, identify dangerous hazards future crews might face, and scour new regions for scientifically valuable geologic features.

“AI systems are going to become critical tools for space exploration that will help humans analyze the millions of images and data sets that future missions will require,” she said. “This work is meant to serve as a bridge between those two worlds, AI and planetary science.”

Mutated immune cells raise red flags in lupus

Scientists at La Jolla Institute for Immunology (LJI) and the University of Washington (UW) have discovered that patients with lupus have unusual mutations that may turn their bodies into battlegrounds.

These mutations are widespread in immune cells called neutrophils. Other immune cells see the mutated neutrophils as a threat—and they try to fight back. This internal battle may contribute to the development of painful inflammation, debilitating joint pain and other serious lupus symptoms throughout the body.

“This may get to the very crux of the disease pathogenesis,” says LJI professor Stephen Schoenberger, Ph.D., who co-led the new Nature study with UW School of Medicine professor Tomas Mustelin, M.D., Ph.D.

Same radical, different paths: X-ray snapshots reveal how neighboring molecules shape its movement

Chemical reactions have their own “impatient molecules.” Unable to stay still even for a moment, they latch onto other molecules indiscriminately. Researchers have now found that even these molecules change where they “sit” and how far they roam depending on who their neighbors are. The findings are expected to help scientists make better medicines and materials by directing reactions only to the desired sites.

A research team led by Professor Kyung Hwan Kim of the Department of Chemistry at Pohang University of Science and Technology, in collaboration with Professor Seung Jun Hwang’s team in the Department of Chemistry at KAIST, captured the first encounters between radicals and neighboring molecules on a timescale of one 10 billionth of a second, or 100 picoseconds.

The team found that the structure of the neighboring molecule changes where a radical resides and the range over which it moves. The study was published in the Journal of the American Chemical Society.

Insect-inspired flying robot bounces back after collisions

Flying insects, such as fruit flies, bees, dragonflies and mosquitoes, can dart through narrow spaces and survive collisions with various objects. In contrast, many flying robots fall, suffer damage or even break down when they hit nearby surfaces or objects.

Researchers at the University of California, Los Angeles (UCLA) and the University of California, Davis (UC Davis) have developed a tiny robot that could better replicate the resilience of flying insects. The new robot, presented in a paper published in Science Robotics, could potentially explore areas that are difficult for other robots or humans to reach, recovering quickly after collisions.

“Our lab has been developing soft robotics for years. We were inspired by how flying insects survive collisions and other physical disturbances,” Qibing Pei, senior author of the paper, told Tech Xplore. “Many insect-sized robots rely on fragile components, which makes operating beyond the laboratory difficult. We saw an opportunity to use electrically responsive polymer materials to create a simpler, more resilient design.”

Comets probably didn’t seed life on Earth after all, new study suggests

The theory that comets delivered the molecular building blocks for life on Earth is a long-standing one, since comets are known to carry many of these molecules. However, a new study challenges this idea.

The researchers, led by the University of Cambridge, found the cometary delivery of these building blocks would be—at best—a ‘one-off fluke,’ and not the steady rain of prebiotic molecules that had been theorized.

Using computer modeling, the researchers determined that comets travel too fast and at too sharp an angle to Earth’s atmosphere for the fragile organic molecules to survive: they would almost certainly vaporize on impact with the surface. However, the researchers also found that another planet in our system—Mars—could be a slightly more promising candidate for cometary delivery of prebiotic molecules, although this is still highly unlikely. The results are published in the journal Scientific Reports.