Spin correlations of the frustrated pyrochlore oxide Tb Ti O have been investigated by using inelastic neutron scattering on single-crystalline samples ( = -0.007, 0.000, and 0.003), which have the putative quantum-spin-liquid (QSL) or electric-quadrupolar ground states. Spin correlations, which are notably observed in nominally elastic scattering, show short-range correlations around points tiny antiferromagnetic Bragg scattering at and Γ points, and pinch-point-type structures around Γ points. The short-range spin correlations were analyzed using a random-phase approximation (RPA) assuming the paramagnetic state and two-spin interactions among Ising spins. These analyses have shown that the RPA scattering intensity well reproduces the experimental data using temperature- and -dependent coupling constants of up to tenth-neighbor site pairs. This suggests that no symmetry breaking occurs in the QSL sample and that a quantum treatment beyond the semiclassical RPA approach is required. Implications of the experimental data and the RPA analyses are discussed.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7592423 | PMC |
J Magn Reson Imaging
January 2025
Department of Radiology, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China.
Background: As ferroptosis is a key factor in renal fibrosis (RF), iron deposition monitoring may help evaluating RF. The capability of quantitative susceptibility mapping (QSM) for detecting iron deposition in RF remains uncertain.
Purpose: To investigate the potential of QSM to detect iron deposition in RF.
J Magn Reson Imaging
January 2025
Department of Radiology, The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine (Shenzhen Traditional Chinese Medicine Hospital), Shenzhen, China.
Background: Multifrequency MR elastography (mMRE) enables noninvasive quantification of renal stiffness in patients with chronic kidney disease (CKD). Manual segmentation of the kidneys on mMRE is time-consuming and prone to increased interobserver variability.
Purpose: To evaluate the performance of mMRE combined with automatic segmentation in assessing CKD severity.
Nat Mater
January 2025
Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY, USA.
Spin waves, or magnons, are essential for next-generation energy-efficient spintronics and magnonics. Yet, visualizing spin-wave dynamics at nanoscale and microwave frequencies remains a formidable challenge due to the lack of spin-sensitive, time-resolved microscopy. Here we report a breakthrough in imaging dipole-exchange spin waves in a ferromagnetic film owing to the development of laser-free ultrafast Lorentz electron microscopy, which is equipped with a microwave-mediated electron pulser for high spatiotemporal resolution.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
January 2025
Faculty of Biotechnology and Food Sciences, Institute of Fermentation Technology and Microbiology, Lodz University of Technology, Wolczanska 171/173, 90-530, Lodz, Poland.
In recent years, there has been a surge in the production of kombucha-a functional beverage obtained via microbial fermentation of tea. However, fresh, unpasteurized kombucha is sensitive to quality deterioration as a result of, among other factors, oxidation. The addition of hops seems to be promising, due to their antioxidative properties, which may improve the stability of kombucha.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Institute of Applied Analysis and Numerical Simulation, University of Stuttgart, Pfaffenwaldring 57, Stuttgart, 70569, Germany.
In this study, we report a comprehensive calculation of the static dipole polarizabilities of group 12 elements using the finite-field approach combined with the relativistic coupled-cluster method, including single, double, and perturbative triple excitations. Relativistic effects are systematically investigated, including scalar-relativistic, spin-orbit coupling (SOC), and fully relativistic Dirac-Coulomb contributions. The final recommended polarizability values are 37.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!