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‘Charge density wave’ linked to atomic distortions in would-be superconductor

What makes some materials carry current with no resistance? Scientists are trying to unravel the complex characteristics. Harnessing this property, known as superconductivity, could lead to perfectly efficient power lines, ultrafast computers, and a range of energy-saving advances. Understanding these materials when they aren’t superconducting is a key part of the quest to unlock that potential.

“To solve the problem, we need to understand the many phases of these materials,” said Kazuhiro Fujita, a physicist in the Condensed Matter Physics & Materials Science Department of the U.S. Department of Energy’s Brookhaven National Laboratory. In a new study just published in Physical Review X, Fujita and his colleagues sought to find an explanation for an oddity observed in a phase that coexists with the superconducting phase of a copper-oxide superconductor.

The anomaly was a mysterious disappearance of vibrational energy from the that make up the material’s crystal lattice. “X-rays show that the atoms vibrate in particular ways,” Fujita said. But as the material is cooled, the X-ray studies showed, one mode of the vibrations stops.

Researchers demonstrate electrical creation and control of antiferromagnetic vortices

A new study has shown for the first time how electrical creation and control of magnetic vortices in an antiferromagnet can be achieved, a discovery that will increase the data storage capacity and speed of next generation devices.

Researchers from the University of Nottingham’s School of Physics and Astronomy have used magnetic imaging techniques to map the structure of newly formed magnetic vortices and demonstrate their back-and-forth movement due to alternating electrical pulses. Their findings have been published in Nature Nanotechnology.

“This is an exciting moment for us, these magnetic vortices have been proposed as information carriers in next-generation memory devices, but evidence of their existence in antiferromagnets has so far been scarce. Now, we have not only generated them, but also moved them in a controllable way. It’s another success for our material, CuMnAs, which has been at the center of several breakthroughs in antiferromagnetic spintronics over the last few years,” says Oliver Amin.

Quantum Computing Algorithm Breakthrough Brings Practical Use Closer to Reality

Out of all common refrains in the world of computing, the phrase “if only software would catch up with hardware” would probably rank pretty high. And yet, software does sometimes catch up with hardware. In fact, it seems that this time, software can go as far as unlocking quantum computations for classical computers. That’s according to researchers with the RIKEN Center for Quantum Computing, Japan, who have published work on an algorithm that significantly accelerates a specific quantum computing workload. More significantly, the workload itself — called time evolution operators — has applications in condensed matter physics and quantum chemistry, two fields that can unlock new worlds within our own.

Normally, an improved algorithm wouldn’t be completely out of the ordinary; updates are everywhere, after all. Every app update, software update, or firmware upgrade is essentially bringing revised code that either solves problems or improves performance (hopefully). And improved algorithms are nice, as anyone with a graphics card from either AMD or NVIDIA can attest. But let’s face it: We’re used to being disappointed with performance updates.

New Quantum Computer Algorithm Unlocks the Power of Atomic-Level Interactions

A novel protocol for quantum computers could reproduce the complex dynamics of quantum materials.

RIKEN researchers have created a hybrid quantum-computational algorithm that can efficiently calculate atomic-level interactions in complex materials. This innovation enables the use of smaller quantum computers or conventional ones to study condensed-matter physics and quantum chemistry, paving the way for new discoveries in these fields.

A quantum-computational algorithm that could be used to efficiently and accurately calculate atomic-level interactions in complex materials has been developed by RIKEN researchers. It has the potential to bring an unprecedented level of understanding to condensed-matter physics and quantum chemistry—an application of quantum computers first proposed by the brilliant physicist Richard Feynman in 1981.

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