A new method turns noise into valuable data to enhance understanding of chemical reactions and material properties with unprecedented detail at the atomic level. The results of this research are now published in Nature.
Category: materials – Page 16
The magic of magnons: Material properties changed non-thermally using light and magnons
“The result was a huge surprise for us. No theory has ever predicted it,” says Davide Bossini.
Not only does the process work—it also has spectacular effects. By driving high-frequency magnon pairs via laser pulses, the physicists succeeded in changing the frequencies and amplitudes of other magnons—and thus the magnetic properties of the material—in a non-thermal way.
“Every solid has its own set of frequencies: electronic transitions, lattice vibrations, magnetic excitations. Every material resonates in its own way,” explains Bossini. It is precisely this set of frequencies that can be influenced through the new process.
Scientists achieve first experimental observation of the transverse Thomson effect
In a new Nature Physics paper, researchers report the first experimental observation of the transverse Thomson effect, a key thermoelectric phenomenon that has eluded scientists since it was predicted over a century ago.
For over a century, thermoelectric effects have formed the foundation of how physicists understand the link between heat and electricity. Our knowledge of how heat and electricity interact within materials is rooted in the Seebeck, Peltier, and Thomson effects, all identified during the 1800s.
The Thomson effect causes volumetric heating or cooling when an electric current and a temperature gradient flow in the same direction through a conductor.
Greatly enhanced nonreciprocal transport in KTaO₃-based interface superconductors linked to parity mixing
Superconductivity is an advantageous property observed in some materials, which entails the ability to conduct electricity without resistance below specific critical temperatures. One particularly fascinating phenomenon observed in some unconventional superconductors is so-called spin-triplet pairing.
In conventional superconductors, electrons form what are known as “Cooper pairs,” pairs of electrons with opposite momentum and spin, a phenomenon referred to as spin-singlet pairing. In some unconventional superconductors, on the other hand, researchers observed a different state known as spin-triplet pairing, which entails the formation of pairs of electrons with parallel spins.
Researchers at Fudan University, RIKEN Center for Emergent Matter Science (CEMS) and other institutes recently observed a significantly enhanced nonreciprocal transport in a class of superconductors known as KTaO3-based interface superconductors, which they proposed could be explained by the co-existence of spin-singlet and spin-triplet states.
You only get one brain: The best helmet material for protecting your noggin
Though participation in sports can have positive impacts both physiologically and socially, extreme sports, like football and roller derby, come with elevated risks. In a 2019 study, over 40% of 498 athletes suffered at least one injury over the course of the year.
These injury rates are even higher in elite cricket—around 70%, with about 13% of all injuries being to the head, neck, and face—pointing to a need for improvements in protective helmets.
In AIP Advances, researchers from Chongqing Jiaotong University and Chongqing No. 7 Middle School compared the performance of three helmet materials under the most common types of impact and loading conditions.
Scientists Create the Impossible: New Compound Challenges Fundamental Principle of Chemistry
Once thought unlikely, this new finding in coordination chemistry could lead to promising advances in catalysis and materials science.
For more than 100 years, the widely accepted 18-electron rule has been a foundational guideline in organometallic chemistry. Now, researchers at the Okinawa Institute of Science and Technology (OIST) have synthesized a new organometallic compound that challenges this principle. They developed a stable 20-electron version of ferrocene, an iron-based metal-organic complex, which could open new directions in chemical research.
“For many transition metal complexes, they are most stable when surrounded by 18 formal valence electrons. This is a chemical rule of thumb on which many key discoveries in catalysis and materials science are based,” said Dr. Satoshi Takebayashi, lead author of the paper published in Nature Communications.