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Twice around to return home: A hidden reset button for spins and qubits

The world is filled with rotating objects—gyroscopes, magnetic spins, and more recently, qubits in quantum computers. For example, the atomic nuclei in our bodies precess at megahertz frequencies inside NMR machines. In practice, it is often desirable to return such a rotating system precisely to its starting point. At first glance, this seems impossible: after an elaborate sequence of twists and wobbles, how could one possibly retrace the path back to the origin?

The astonishing answer is that it is always possible. No matter how tangled the history of rotations, there exists a simple recipe: rescale the driving force and apply it twice. A single application is never sufficient, but applying this doubled, rescaled force guarantees an exact return. Under this operation, the spin—or the qubit, or any rotor—will unfailingly come home.

This discovery was made by Distinguished Professor Tsvi Tlusty from the Department of Physics at UNIST and Jean-Pierre Eckmann from the University of Geneva, Switzerland. Their study, published in Physical Review Letters on October 1, 2025, reveals that, despite their apparent complexity, rotations conceal a fundamental order.

Time crystals could power future quantum computers

A glittering hunk of crystal gets its iridescence from a highly regular atomic structure. Frank Wilczek, the 2012 Nobel Laureate in Physics, proposed quantum systems––like groups of particles––could construct themselves in the same way, but in time instead of space. He dubbed such systems time crystals, defining them by their lowest possible energy state, which perpetually repeats movements without external energy input. Time crystals were experimentally proved to exist in 2016.

Framework models light-matter interactions in nonlinear optical microscopy to determine atomic structure

Materials scientists can learn a lot about a sample material by shooting lasers at it. With nonlinear optical microscopy—a specialized imaging technique that looks for a change in the color of intense laser light—researchers can collect data on how the light interacts with the sample, and through time-consuming and sometimes expensive analyses, characterize the material’s structure and other properties.

Now, researchers at Pennsylvania State University have developed a that can interpret the nonlinear optical microscopy images to characterize the material in microscopic detail.

The team has published its approach in the journal Optica.

Rigorous approach quantifies and verifies almost all quantum states

Quantum information systems, systems that process, store or transmit information leveraging quantum mechanical effects, could, in principle, outperform classical systems in some optimization, computational, sensing, and learning tasks. An important aspect of quantum information science is the reliable quantification of quantum states in a system, to verify that they match desired (i.e., target) states.

Why some quantum materials stall while others scale

People tend to think of quantum materials—whose properties arise from quantum mechanical effects—as exotic curiosities. But some quantum materials have become a ubiquitous part of our computer hard drives, TV screens, and medical devices. Still, the vast majority of quantum materials never accomplish much outside of the lab.

What makes certain commercial successes and others commercially irrelevant? If researchers knew, they could direct their efforts toward more promising materials—a big deal since they may spend years studying a single material.

Now, MIT researchers have developed a system for evaluating the scale-up potential of quantum materials. Their framework combines a material’s quantum behavior with its cost, supply chain resilience, environmental footprint, and other factors.

New Models Show How Solar ‘Tornadoes’ Could Wreak Havoc on Earth

Weather forecasting is a powerful tool. During hurricane season, for instance, meteorologists create computer simulations to forecast how these destructive storms form and where they might travel, which helps prevent damage to coastal communities.

When you’re trying to forecast space weather, rather than storms on Earth, creating these simulations gets a little more complex.

To simulate space weather, you would need to fit the Sun, the planets, and the vast empty space between them in a virtual environment, also known as a simulation box, where all the calculations would take place.

Scientists build artificial neurons that work like real ones

There are a wide range of applications for Fu and Yao’s new neuron, from redesigning computers along bio-inspired, and far more efficient principles, to electronic devices that could speak to our bodies directly.

“We currently have all kinds of wearable electronic sensing systems,” says Yao, “but they are comparatively clunky and inefficient. Every time they sense a signal from our body, they have to electrically amplify it so that a computer can analyze it. That intermediate step of amplification increases both power consumption and the circuit’s complexity, but sensors built with our low-voltage neurons could do without any amplification at all.”

The secret ingredient in the team’s new low-powered neuron is a protein nanowire synthesized from the remarkable bacteria Geobacter sulfurreducens, which also has the superpower of producing electricity. Yao, along with various colleagues, have used the bacteria’s protein nanowires to design a whole host of extraordinary efficient devices: a biofilm, powered by sweat, that can power personal electronics; an “electronic nose” that can sniff out disease; and a device, which can be built of nearly anything, that can harvest electricity from thin air itself.

Back to the future: Is light-speed analog computing on the horizon?

Scientists have achieved a breakthrough in analog computing, developing a programmable electronic circuit that harnesses the properties of high-frequency electromagnetic waves to perform complex parallel processing at light-speed.

The discovery points to a new era of computing that operates far beyond the limits of conventional digital electronics, using less energy, while performing massive calculations.

The study, “Programmable circuits for analog matrix computations,” has been published in Nature Communications.

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