Physics Magazine

Researchers have devised a “reset or reload” protocol that mitigates the loss of atoms from devices that use cold, trapped atoms for quantum computing. The method held up through 41 successive operations. physics.aps.org/articles/v18...

The Higgs field hides electroweak symmetry and gives masses to the electroweak bosons, W and Z. New results from the ATLAS Collaboration support the idea that the quark and charged-lepton masses are also the work of the Higgs field. physics.aps.org/articles/v18...

In 1927 Einstein devised a thought experiment to expose what he believed was contradictory character of quantum complementarity. Researchers have now performed the experiment in a way that could explore other, less established aspects of quantum mechanics. physics.aps.org/articles/v18...

Within femtoseconds, a photon absorbed by a molecule can cause electrons to jump between energy levels, atoms to vibrate, and chemical bonds to rearrange. Now researchers have shown that ultrafast electron diffraction can track those perturbations. physics.aps.org/articles/v18...

The fractional quantum Hall effect comes with fractionally charged quasiparticles called anyons. Curiously, anyon charges are found to be multiples of their expected values. Now theorists have a solution: anyons bind together into “molecules.” physics.aps.org/articles/v18...

Two independent groups have proposed a new class of 2D multiferroic materials that could find applications in spin-based computers, sensors, and energy-harvesting devices. physics.aps.org/articles/v18...

Surprisingly, the size distributions of shattered fragments and spattered drops follow a simple power law. Now researchers have shown that the statistical regularities of fragmentation can emerge from a combination of maximum randomness and kinematic constraints. physics.aps.org/articles/v18...

Researchers have trapped molecules in the standing wave created by a laser field in a cavity. By mitigating Doppler broadening, the technique enhances high-precision molecular spectroscopy, which is used to search for new physics. physics.aps.org/articles/v18...

Devised 40 years ago, the Leggett-Garg inequality tests whether a system’s evolution over time can be described by classical realism. Now researchers have shown that this limit can be surpassed by a quantum system evolving under a superposition of operations. physics.aps.org/articles/v18...

Researchers have imaged and stretched a gold nanowire while also tracking its electrical conductance. The two-for-one experiment enabled them to pinpoint the width at which ballistic transport becomes operative. physics.aps.org/articles/v18...

Researchers have placed a precise amount of charge on a microparticle trapped in optical tweezers. Their technique could lead to better understanding of the effects of charged particles on lightning and clouds. physics.aps.org/articles/v18...

Researchers have built and studied a tiny engine in the form of a levitated glass microparticle. The engine’s counterintuitive thermodynamics may help explain the nonequilibrium behavior of various biological systems. physics.aps.org/articles/v18...

Researchers have analyzed a hypothetical scenario in which three Cooper pairs tunnel simultaneously in a four-terminal Josephson junction. Such a process is important because it could facilitate new functionalities in quantum technologies. physics.aps.org/articles/v18...

The extent of a particle’s wave function depends on the particle’s mass and environment. Researchers have developed an optical method that sheds light on this dependence for single hydrogen and deuterium molecules trapped in a superfluid helium nanodroplet. physics.aps.org/articles/v18...

Researchers have determined the entropy of a double quantum dot by measuring how much energy is needed to pack in an additional electron. Their method could be used to determine quantities that are even harder to measure, such as exotic quasiparticle couplings.

Quantum magic is a property of certain quantum states that enables operations outside the fault-tolerant, classically accessible set. Last year two theorists answered the long-standing question of how to reliably measure this important property.

The Costs of Quantum Timekeeping Experiments reveal the surprisingly large amount of entropy—and thus heat—generated by a clock that could be part of a quantum processor.

Researchers made a clock from two single-electron traps known as quantum dots and used it to measure the entropy produced by the act of recording a clock’s ticks. They found that this process generates far more entropy and heat than the clock’s quantum operations.

Quantum Scars Unmasked A new approach finds useful patterns called quantum scars in the complex dynamics of quantum many-body systems.

A quantum system's decoherence can be delayed by contriving to have its dynamics linger in persistent, preexisting patterns called quantum scars. Researchers have now demonstrated a general theoretical method for finding these scars.

Measuring the Sun’s Opacity Experiments with oxygen plasma at extreme densities and temperatures give new transparency to our picture of the Sun’s interior.

Researchers have measured the opacity of one of the Sun’s most important elements for radiation transport—oxygen—at densities and temperatures high enough to potentially resolve a persistent discrepancy between theory and observation.

Phase Transition Proceeds Slowly, Then All at Once Adding extra atoms between sheets of PdSe doesn’t affect the material’s layered structure—until it does.

Researchers have found that stacks of the 2D semiconductor palladium diselenide keep their original form as the interlayer spaces are packed with additional Pd atoms—until the stack switches abruptly to a new and thicker 3D structure.

Making Fresh Radionuclides with Leftover Gamma Rays Photons in high-energy probe beams that pass through their intended target can be “reused” for making promising nuclides in nuclear medicine, new experiments show.

Copper-67 is a promising radionuclide for treating cancer. Researchers have shown they can make it by piggy-backing on particle physics experiments.

A Quantum Microscope Reveals Water Breaking Apart A scheme combining a scanning probe microscope with a quantum sensor can locally trigger water dissociation and observe the elementary steps of such a reaction.

Researchers have combined the quantum sensing of nitrogen vacancy centers with the atomic resolution of scanning probe microscopy. To demonstrate this new capability, the team followed the individual steps of an important chemical process: the dissociation of water molecules on a surface.

Zeroing In on Zero-Point Motion Inside a Crystal A nanocrystal cooled to near absolute zero produces an unexpected light emission, which is shown to arise from quantum fluctuations in the crystal’s atomic lattice.

Researchers have identified a new low-temperature emission effect in nanocrystals. Related to zero-point motion, the effect could prove useful in cooling nanocrystals to lower temperatures than previously possible.

Spin-Phase Detector Experiments demonstrate a device-friendly technique that can measure the spin phase in magnets with helical magnetic ordering.

Helimagnets’ spin phase—a parameter describing the spin direction at one end of the helical pattern—could be used to store information. That prospect could be closer now that researchers have reported a new way to measure spin phase.

Shining Light on Antiferromagnets Researchers use a magneto-optical technique to image and manipulate magnetic domains in a chiral antiferromagnet, opening new routes for spin-based electronics.

The cancelling spins of antiferromagnets bestow resistance to stray magnetic fields but they also make the materials hard to probe or control. Now researchers have shown that light provides a powerful new way to image antiferromagnetic domains and even to manipulate them.

Constraints on Quantum-Advantage Experiments Due to Noise Current quantum computers are noisy, which places limitations on the type of quantum machine needed to outpace classical computers.

Current quantum processors have profound physical limitations, mostly related to noise. New research shows that the possibility of noisy quantum computers outdoing classical computers may be restricted to a “Goldilocks zone” between too few and too many qubits.

Active Matter Gets Solid Researchers have determined the mechanical properties of a tiny beam made of active particles, laying the groundwork for future micromachines.

Coaxing tiny, self-propelled particles into cohesive structures provides one route to making micromachines. Taking a step in that direction, researchers have measured and analyzed the mechanical properties of materials assembled from active particles.

Spooky Sensor at a Distance How do spiders pounce so quickly on hapless prey entangled in their webs? New research suggests that elaborate web “decorations” help transmit the wiggling signal from a trapped bug.

Spider webs often feature zigzagging layers of tough silk whose purpose has puzzled biologists. Now physicists have a solution. The structures spread prey-induced vibrations out through the web, helping spiders to locate their trapped victims.

A Shortcut to a Ground State Theorists have proposed a universal recipe for trying to quickly prepare a system in a desired ground state without exciting it.

Two groups of researchers have independently devised a new recipe for quickly driving a generic quantum system into a desired ground state. Compared with previous recipes, it doesn't require as much detailed knowledge of the system.

How Confined Objects Arrange Themselves A collection of mutually repelling objects can be forced into the same arrangement, whether they are magnets, soap bubbles, or hard spheres.

Push together a small number of mutually repelling particles and they’ll adopt configurations that depend on the specifics of the interaction and the container. Researchers have now shown that a wide range of particle types can be coaxed into the same set of configurations.