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Quasicrystals Grow Smoothly Around Obstacles

Large-scale obstacles to crystal growth can throw the whole lattice off kilter, but quasicrystals can accommodate them without losing their atomic-scale order.

When a growing crystal encounters an obstacle, the orderly array of atoms may have to adjust in ways that create lattice defects or large-scale rearrangements. But a research team has found through experiments that peculiar materials called quasicrystals can take such disruptions in stride [1] The quasicrystalline lattice, which is orderly but not periodic, can accommodate obstacles without sacrificing its order, thanks to a type of rearrangement unique to quasicrystals. The work suggests the possibility of making quasicrystalline metal alloys that are more durable than conventional alloys.

Quasicrystals, discovered in 1984, are typically compounds composed of metals such as aluminum, nickel, and manganese. X-ray diffraction seems to show that their atomic lattices have symmetries that aren’t permitted in conventional crystals, such as pentagonal or decagonal symmetry. But these symmetries can exist in small regions because quasicrystals are not conventional crystals—you can’t shift the atomic lattice in space and then superimpose it exactly on the original lattice.

Vortices in ultralight dark matter halos could reveal new clues to cosmic structure

The nature of dark matter remains one of the greatest mysteries in cosmology. Within the standard framework of non-collisional cold dark matter (CDM), various models are considered: WIMPs (Weakly Interacting Massive Particles, with masses of around 100 GeV/c2), primordial black holes, and ultralight axion-like particles (mass of 10-22 to 1 eV/c2). In the latter case, dark matter behaves like a wave, described by a Schrödinger equation, rather than as a collection of point particles. This generates specific behaviors at small scales, while following standard dynamics (CDM) at large scales.

Philippe Brax and Patrick Valageas, researchers at the Institute of Theoretical Physics, studied models of ultralight cold dark matter with repulsive self-interactions, whose dynamics are described by a non-linear variant of the Schrödinger equation, known as the Gross-Pitaevskii equation, also encountered in the physics of superfluids and Bose-Einstein condensates. In their work, the authors follow the formation and dynamics of particular structures, called “vortices” (whirlpools) and “solitons” (cores in hydrostatic equilibrium), within halos of rotating ultralight dark matter.

The papers are published in the journal Physical Review D.

Diamond probe measures ultrafast electric fields with femtosecond precision

Researchers at University of Tsukuba have successfully measured electric fields near the surfaces of two-dimensional layered materials with femtosecond temporal and nanometer spatial resolution. They employed a diamond containing a nitrogen-vacancy center—a lattice defect—as a probe within an atomic force microscope, enabling atomic-scale spatial precision.

When nitrogen is incorporated as an impurity in a , the absence of a neighboring carbon atom forms a nitrogen-vacancy (NV) center. Applying an to diamond containing NV centers modifies its , a phenomenon known as the electro-optic (EO) effect. Notably, this effect has not been observed in pure diamond alone.

In previous work, the research team used a to detect lattice vibrations in diamond with high sensitivity by measuring the EO effect in high-purity diamond containing NV centers. These results demonstrated that diamond can act as an ultrafast EO crystal and serve as a probe—termed a diamond NV probe—for measuring electric fields.

Unified Equation: A Berry-Curvature Theory of Quantum Gravity, Entanglement, and Mass Emergence

Many Thanks to Sabine Hossenfelder for giving me puzzles.

What if everything — gravity, light, particles, and even the flow of time — came from a single equation? In Chavis Srichan’s Unified Theory, the universe isn’t built from matter, but from the curvature of entanglement — the twists and turns of quantum information itself. Space, energy, and even consciousness are simply different ways this curvature vibrates.

The One Equation.

At the smallest scale, every motion and interaction follows one rule:

[D_μ, D_ν]Ψ = (i/ħ) [(8πG/c⁴)⟨T_μν(Ψ)⟩ − Λ_q g_μν + λ ∇_μ∇_ν S]Ψ

It means that the “shape” of space itself bends in response to energy and information — and that same bending is quantum mechanics, gravity, and thermodynamics combined.

Mass: When Curvature Loops Back.

Simplified Sachdev-Ye-Kitaev model simulated on trapped-ion quantum computer

The simulation of strongly interacting many-body systems is a key objective of quantum physics research, as it can help to test the predictions of physics theories and yield new valuable insight. Researchers at Quantinuum, a quantum computing company, recently simulated a simplified version of a well-known theoretical model, the so-called Sachdev-Ye-Kitaev (SYK) model, using a trapped-ion quantum computer and a previously introduced randomized quantum algorithm.

Their simulation, outlined in a paper published on the arXiv preprint server, improves the present understanding of chaotic quantum systems that cannot be simulated using classical computers. In the future, their work could contribute to the simulation of other complex quantum systems and .

“We were interested in the SYK model for two reasons: on one hand it is a prototypical model of strongly interacting fermions in condensed matter physics, and on the other hand it is the simplest toy model for studying in the lab via the holographic duality,” said Enrico Rinaldi, Lead R&D Scientist at Quantinuum and senior author of the paper.

Sean Carroll: Can we ever escape the logic of a clockwork universe?

What if the universe is a machine, and every moment in our past, present, and future is already encoded in the positions of its particles?

Physicist Sean Carroll explores the unsettling implications of classical mechanics, from Newton’s laws to Laplace’s thought experiment, showing how determinism challenges the very idea of free will.

Is This the End of the Silicon Era? Scientists Unveil World’s First 2D Computer

Researchers at Penn State have developed the first silicon-free computer using atom-thin materials. This breakthrough could reshape the future of electronics, paving the way for ultra-efficient, miniaturized computing devices. Silicon has long been the foundation of semiconductor technology that

Quantum radio antenna uses Rydberg states for sensitive, all-optical signal detection

A team from the Faculty of Physics and the Center for Quantum Optical Technologies at the University of Warsaw has developed a new type of all-optical radio receiver based on the fundamental properties of Rydberg atoms. The new type of receiver is not only extremely sensitive, but also provides internal calibration, and the antenna itself is powered only by laser light.

The results of the work, in which Sebastian Borówka, Mateusz Mazelanik, Wojciech Wasilewski and Michał Parniak participated, were published in Nature Communications. They open a new chapter in the technological implementation of quantum sensors.

In today’s society, huge amounts of digital information are transmitted around us every second. Much of it is transmitted by radio, i.e. using . For a very long time, amplitude modulation has been used to encode information, sending stronger and weaker waves.

Old-school material could power quantum computing and cut data center energy use

A new twist on a classic material could advance quantum computing and make modern data centers more energy efficient, according to a team led by researchers at Penn State.

Barium titanate, first discovered in 1941, is known for its powerful electro-optic properties in bulk, or three-dimensional, crystals. Electro-optic materials like act as bridges between electricity and light, converting signals carried by electrons into signals carried by photons, or particles of light.

However, despite its promise, barium titanate never became the industry standard for electro-optic devices, such as modulators, switches and sensors. Instead, lithium niobate—which is more stable and easier to fabricate, even if its properties don’t quite measure up with those of barium titanate—filled that role instead. But by reshaping barium titanate into ultrathin strained thin films, this could change, according to Venkat Gopalan, Penn State professor of materials science and engineering and co-author of the study published in Advanced Materials.

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