One intriguing method that could be used to form the qubits needed for quantum computers involves electrons hovering above liquid helium. But it wasn’t clear how data in this form could be read easily.
Now RIKEN researchers may have found a solution. Their work is published in the journal Physical Review Letters.
During chemical reactions, atoms in the reacting substances break their bonds and re-arrange, forming different chemical products. This process entails the movement of both electrons (i.e., negatively charged particles) and nuclei (i.e., the positively charged central parts of atoms). Valence electrons are shared and re-arranged between different atoms, creating new bonds.
The movements of electrons and nuclei during chemical reactions are incredibly fast, in many cases only lasting millionths of a billionth of a second (i.e., femtoseconds). Yet reliably tracking and understanding these movements could help to shed new light on how specific molecules are formed, as well as on the underpinnings of quantum mechanical phenomena.
Researchers at Shanghai Jiao Tong University recently introduced a new approach to observe chemical reactions as they unfold, precisely tracking the movement of electrons and atomic nuclei as a molecule breaks apart. This strategy, outlined in a paper published in Physical Review Letters, was successfully used to image the photodissociation of ammonia (NH₃), the process in which a NH₃ molecule absorbs light and breaks down into smaller pieces.
A new framework for understanding the nonmonotonic temperature dependence and sign reversal of the chirality-related anomalous Hall effect in highly conductive metals has been developed by scientists at Science Tokyo. This framework provides a clear picture of the unusual temperature dependence of chirality-driven transport phenomena, forming a foundation for the rational design of next-generation spintronic devices and magnetic quantum materials.
Magnetic materials exhibit a variety of intriguing properties during their magnetization process that reflect their magnetic states and excitations. These properties are studied by applying an external magnetic field to the material, producing the magnetization curve. Magnetic metals additionally demonstrate rich behavior in transport phenomena, referring to the flow of charge, heat, or spin under the influence of magnetic fields.
However, some of these behaviors are difficult to probe using the magnetization curve. The anomalous Hall effect (AHE) is one such effect. In the AHE, when an electric current passes through a magnetic metal, a voltage perpendicular to the current arises even in the absence of an external magnetic field. By contrast, in the traditional Hall effect, such a transverse voltage appears only when an external magnetic field is applied.
Researchers at the Department of Energy’s Oak Ridge National Laboratory are pioneering the design and synthesis of quantum materials, which are central to discovery science involving synergies with quantum computation. These innovative materials, including magnetic compounds with honeycomb-patterned lattices, have the potential to host states of matter with exotic behavior.
Using theory, experimentation and computation, scientists synthesized a magnetic honeycomb of potassium cobalt arsenate and conducted the most detailed characterization of the material to date. They discovered that its honeycomb structure is slightly distorted, causing magnetic spins of charged cobalt atoms to strongly couple and align.
Tuning these interactions, such as through chemically modifying the material or applying a large magnetic field, may enable the formation of a state of matter known as a quantum spin liquid. Unlike permanent magnets, in which spins align fixedly, quantum spins do not freeze in one magnetic state.
Scientists at the X-ray free-electron laser SwissFEL have realized a long-pursued experimental goal in physics: to show how electrons dance together. The technique, known as X-ray four-wave mixing, opens a new way to see how energy and information flow within atoms and molecules. In the future, it could illuminate how quantum information is stored and lost, eventually aiding the design of more error-tolerant quantum devices. The findings are reported in Nature.
Much of the behavior of matter arises not from electrons acting alone, but from the ways they influence each other. From chemical systems to advanced materials, their interactions shape how molecules rearrange, how materials conduct or insulate and how energy flows.
In many quantum technologies —not least quantum computing—information is stored in delicate patterns of these interactions, known as coherences. When these coherences are lost, information disappears—a process known as decoherence. Learning how to understand and ultimately control such fleeting states is one of the major challenges facing quantum technologies today.
Building large-scale quantum technologies requires reliable ways to connect individual quantum bits (qubits) without destroying their fragile quantum states. In a new theoretical study, published in npj Computational Materials, researchers show that crystal dislocations—line defects long regarded as imperfections—can instead serve as powerful building blocks for quantum interconnects.
Using advanced first-principles simulations, a team led by Prof. Maryam Ghazisaeidi at The Ohio State University and Prof. Giulia Galli at the University of Chicago Pritzker School of Molecular Engineering (UChicago PME) and Chemistry Department demonstrated that nitrogen-vacancy (NV) centers in diamond, a leading solid-state qubit platform, can be attracted to dislocations and retain—and in some cases improve—their quantum properties when positioned near these line defects.
“Because dislocations form quasi-one-dimensional (1D) structures extending through a crystal, they provide a natural scaffold for arranging qubits into ordered arrays,” said co-first author Cunzhi Zhang, a UChicago PME staff scientist in the Galli Group.
Wormholes are often imagined as tunnels through space or time—shortcuts across the universe. But this image rests on a misunderstanding of work by physicists Albert Einstein and Nathan Rosen.
In 1935, while studying the behavior of particles in regions of extreme gravity, Einstein and Rosen introduced what they called a “bridge”: a mathematical link between two perfectly symmetrical copies of spacetime. It was not intended as a passage for travel, but as a way to maintain consistency between gravity and quantum physics. Only later did Einstein–Rosen bridges become associated with wormholes, despite having little to do with the original idea.
But in new research published in Classical and Quantum Gravity, my colleagues and I show that the original Einstein–Rosen bridge points to something far stranger—and more fundamental—than a wormhole.
A research team has developed a hierarchical-shell perovskite nanocrystal technology that simultaneously overcomes the long-standing instability of metal-halide perovskite emitters while achieving record-breaking quantum yield, operational stability, and scalability. This work paves the way for next-generation vivid-color display technologies.
The research is published in the journal Science as a cover article.
The team was led by Professor Tae-Woo Lee (Department of Materials Science and Engineering, Seoul National University, Republic of Korea & SN Display Co., Ltd).
Different atoms and ions possess characteristic energy levels. Like a fingerprint, they are unique for each species. Among them, the atomic ion 173 Yb+ has attracted growing interest because of its particularly rich energy structure, which is promising for applications in quantum technologies and searches for so-called new physics. On the flip side, the complex structure that makes 173 Yb+ interesting has long prevented detailed investigations of this ion.
Now, researchers from PTB, TU Braunschweig, and the University of Delaware have taken a closer look at the ion’s energy structure. To achieve this, they trapped a single 173 Yb+ ion and developed methods for preparing and detecting its energy state despite the complicated energy structure. This enabled high-resolution laser and microwave spectroscopy. The research is published in the journal Physical Review Letters.
In particular, the researchers investigated energy shifts arising from interactions between the nucleus and its surrounding electrons, also called hyperfine structure. Combined with first-principle theory calculations, the precise measurement results yielded new information about the ion’s nucleus.