Rare-earth nickelates are known to undergo a metal-to-insulator phase transition as temperature decreases, the mechanism of which is not well understood. Here, researchers observed a new low-temperature phase that’s both metallic and antiferromagnetic—an unusual combination with potential value in spintronics. Read more »
Charge Density Wave Found in Magnetic Kagome Crystal
Researchers discovered a wave-like charge order in a magnetic material with a “kagome” geometric structure and obtained clues to the order’s origins in the material’s electronic structure. By helping to connect certain structures with emergent quantum properties, the work brings us a step closer to the goal of creating materials by design. Read more »
What Drives Electron–Hole Asymmetry in Graphene?
Using the ALS, researchers determined that interactions between electrons are what give rise to the divergent effects observed when graphene is doped with electrons versus holes. A better understanding of this electron–hole asymmetry could lead to new avenues for generating exotic material phases, including unconventional superconductivity. Read more »
Scientists Discover ‘Secret Sauce’ Behind Exotic Properties of New Quantum Material
Kagome metals have long mystified scientists for their ability to exhibit collective behavior when cooled below room temperature. A research team has discovered that the kagome electrons’ unusual synchronicity is due to another behavior known as an electronic singularity, or the Van Hove singularity, which involves the relationship between the electrons’ energy and velocity. Read more »
The Elusive Electronic Structure of Liquid Metals Unveiled
Over 50 years ago, renowned physicists formulated theoretical models for the electronic structure of liquid metals. Now, for the first time, researchers observed the distinct spectral features predicted by those models, at the interface of a crystalline insulator (black phosphorus) and disordered dopants (alkali metals). Read more »
Autonomous Data Acquisition for Scientific Discovery
Researchers at large scientific facilities such as the ALS have applied a robust machine-learning technique to automatically optimize data gathering for a variety of experimental techniques. The work promises to enable experiments with large, complex datasets to be run more quickly, efficiently, and with minimal human intervention. Read more »
Graphene Outperforms Metal Junctions for 2D Semiconductors
Researchers found that graphene performs ten times better than metal in transmitting a photoinduced current across interfaces with 2D semiconductors. Nanoscale-resolution band-structure measurements provided a deeper understanding of charge transport in these systems and will help in engineering more efficient contacts. Read more »
The Flat Band in Magic-Angle Graphene Visualized
Researchers visualized flat band structures associated with exotic electronic phases in stacked graphene layers offset from each other by a “magic angle.” The work corroborates theoretical predictions and has significant implications for phenomena of technological and fundamental interest, such as topological phases and superconductivity. Read more »
A Scalable Platform for Two-Dimensional Metals
Using a new method for stabilizing a two-dimensional (2D) metal on a large-area platform, researchers probed the origins of the material’s superconductivity. The work represents a notable milestone in advancing 2D materials toward broad applications in topological computing, advanced optics, and molecular sensing. Read more »
Elusive Kagome Electronic Structures Revealed
Electronic-structure studies showed that both infinitely light and infinitely massive particles coexist in a material with a star-shaped (kagome) crystal lattice. The material’s rich array of electronic behaviors shows promise for future spintronic applications and represents a new frontier for studying exotic phases of matter. Read more » 