Publications by authors named "A Podlesnyak"
Cobalt-based pyroxenes: A new playground for Kitaev physics.
Proc Natl Acad Sci U S A
October 2024
Article Synopsis
- Recent research shows that cobaltites may serve as a valuable avenue for studying Kitaev physics in honeycomb structures and the Ising model in weakly linked chains.
- The study investigates the magnetic properties of SrCoGeO using neutron scattering, ab initio methods, and linear spin-wave theory to propose a modified Kitaev model for the interactions in this material.
- Findings indicate that external magnetic fields can shift the material's magnetic ordering and suggest modified pyroxenes could offer new insights into Kitaev physics.
The extraordinary properties of the Kitaev model have motivated an intense search for new physics in materials that combine geometrical and bond frustration. In this Letter, we employ inelastic neutron scattering, spin wave theory, and exact diagonalization to study the spin dynamics in the perfect triangular-lattice antiferromagnet (TLAF) CsCeSe_{2}. This material orders into a stripe phase, which is demonstrated to arise as a consequence of the off-diagonal bond-dependent terms in the spin Hamiltonian.
View Article and Find Full Text PDFArticle Synopsis
- The S=1/2 triangular lattice antiferromagnet (TLAF) model showcases complex quantum magnetic behavior influenced by exchange anisotropy, specifically in BaLaCoTeO (BLCTO), which shows 120° magnetic order below 3.26K.
- Using inelastic neutron scattering (INS) and advanced calculations, the study identified strong easy-plane XXZ anisotropy and observed a significant energy continuum in spin excitations that indicates a confinement length much larger than the lattice spacing.
- The findings suggest a connection between the excitation spectrum's unique characteristics and higher-order van Hove singularities, providing valuable insights into anisotropic magnetic systems.
Neutron diffraction and spectroscopy offer unique insight into structures and properties of solids and molecular materials. All neutron instruments located at the various neutron sources are distinct, even if their designs are based on similar principles, and thus, they are usually less familiar to the community than commercial X-ray diffractometers and optical spectrometers. Major neutron instruments in the USA, which are open to scientists around the world, and examples of their use in coordination chemistry research are presented here, along with a list of similar instruments at main neutron facilities in other countries.
View Article and Find Full Text PDFThe magnetic properties of spinel nanoparticles can be controlled by synthesizing particles of a specific shape and size. The synthesized nanorods, nanodots and cubic nanoparticles have different crystal planes selectively exposed on the surface. The surface effects on the static magnetic properties are well documented, while their influence on spin waves dispersion is still being debated.
View Article and Find Full Text PDF