Sliding droplets point to charging mechanism beyond mobile ions

Whether on a windowpane at home or during the industrial cleaning of computer chips: droplets sliding over solid surfaces become electrically charged. Yet the physical mechanism behind this charging remains a subject of debate. This charging is usually attributed to the exchange of charged particles (ions) at the interface between the droplet and the surface. […]

How some cyclists paradoxically start ‘from rest’ with a non-zero velocity

Some track cyclists appear to break the rules of physics, but a new study, published in the journal Royal Society Open Science, has created a model explaining the illusion. The results suggest that a quick succession of well-timed moves can help cyclists get a head start without actually breaking the rules of the race or […]

Dual findings reveal how to control coherence in plasmonic nanolasers

Researchers at the University of Eastern Finland have uncovered two complementary mechanisms that govern coherence in miniaturized lasers composed of metallic nanoparticle arrays incorporated into an optical gain material, also known as plasmonic lattice lasers.

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Heating mica to 200°C reveals friction independent of sliding speed

Through joint research with the U.S. Geological Survey and the University of Tokyo, NIMS for the first time experimentally demonstrated friction completely independent of sliding velocity—an ideal that had never been realized—by heating mica, a layered oxide also used as a lubricant material, to 200°C (392°F). NIMS also clarified that this is caused by the […]

New simulations link unusual particle diffusion to yielding in soft jammed matter

Soft materials such as colloidal suspensions, emulsions, foams and gels often display complex and unusual behaviors compared with ordinary solids or liquids. From a mechanical point of view, for instance, they can resist deformation like solids, but they can also start to flow like liquids when a sufficiently strong external drive is applied. This transition […]

Study explores new photonics advance: Topology imprinting in nonlinear metasurfaces

Light is traditionally described by properties such as wavelength, amplitude, phase and polarization. Advances in optics have shown that light can also be shaped into complex spatial patterns known as structured light, enabling new ways to carry information and interact with matter for applications in imaging, optical communications and information processing.

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Disordered atoms steer shared light pulses by matching motion and timing

A research team at the Institute of Applied Physics at TU Darmstadt has shown for the first time that atoms that are completely disordered and in constant motion can nevertheless emit jointly directed light preferentially in one direction—even though neither the atoms nor their environment exhibit a direction—and that the strength of this asymmetry can […]

Magnets could help quantum computers talk to each other, says researcher

Xufeng Zhang is using magnets to make computers more power efficient at the quantum level. The Northeastern professor of electrical and computer engineering recently published two papers highlighting small-scale magnetic systems he and his team developed that could help make computers much more power efficient in the future.

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Novel particle beam could challenge Einstein’s theory of gravity

Does gravity act equally on all particles in the universe, or are there differences between ordinary and exotic matter? Physics professor Anna Soter and her team at ETH Zurich and the Paul Scherrer Institute (PSI) in Villigen are investigating this question. “We have taken an important step toward carrying out an exciting experiment on this […]

From atomic vibrations to laboratory mechanics: Bridging 20 orders of magnitude in time

How can we predict the way a real material, such as a polymer, responds mechanically over timescales ranging from the ultrafast motion of atoms to the slow deformations measured in a laboratory? This is a deceptively difficult problem.

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Getting photons into shape for reliable quantum communication

The vast majority of modern quantum technologies—from quantum cryptography to the quantum internet to the quantum computer—rely on one essential element: the transmission of photons. Two qubits (two atoms, for example) exchange information: One qubit emits a photon, and the other qubit absorbs it.

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Speedy electrons for brilliant laser light: Research paves the way for compact, inexpensive free-electron lasers

Extremely short, intense light flashes are in high demand to investigate atoms, molecules and new materials. Free-electron lasers (FELs) produce these flashes. But around the world, beam time available at large-scale user facilities is in short supply, and waiting times are long.

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Unified framework shows thermoelectric performance depends on more than the material itself

Thermoelectric materials can directly convert heat into electricity, making them promising for recovering waste heat from factories, vehicles and other sources. They can also transport heat when an electric current is applied through a phenomenon known as the Peltier effect. These properties have attracted considerable interest in energy-saving technologies and thermal management.

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Ultracold cesium atoms reveal Bethe strings predicted nearly a century ago

In 1931, physicist Hans Bethe predicted that, in certain one-dimensional quantum systems, particles can bind together to form multi-particle states known as Bethe strings. Unlike ordinary molecules, which are held together by chemical bonds, Bethe strings arise purely from interactions between particles and exist only in one dimension. For decades, Bethe strings remained primarily a […]

Physicists help uncover ‘spooky’ quantum effect in the Large Hadron Collider

Physicists at the University of Oxford have helped confirm that one of the strangest phenomena in physics—quantum entanglement—occurs even among some of the heaviest and most fleeting particles ever created. The discovery, made using the world’s most powerful particle collider at CERN, has been published in Physical Review Letters.

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