Related papers: The Exchange Parameters in Lanthanum Manganites
We perform inelastic neutron scattering measurements on the molecular nanomagnet Mn_12-acetate to measure the excitation spectrum up to 45meV (500K). We isolate magnetic excitations in two groups at 5-6.5meV (60-75K) and 8-10.5meV…
We report a novel practical method to determine exchange parameters by using experimental susceptibility data in a relatively narrow temperature region and a low order high-temperature-expansion equation. This method is applied to a square…
The phase diagram of the multivalent manganites $\rm La_{1-x}Ca_xMnO_3$, in space of temperature and doping $x$, is a challenge for the theoretical physics. It is an important test for the model used to study these compounds and the method…
Heterostructures of mixed-valence manganites are still under intense scrutiny, due to the occurrence of exotic quantum phenomena linked to electronic correlation and interfacial composition. For instance, if two anti-ferromagnetic…
The magnetic susceptibility and spin-spin correlation of the double-exchange model for doped manganites are investigated through the Monte Carlo calculations on the three-dimensional lattice model. Deviations of the susceptibility from the…
In the multiferroic hexagonal manganite HoMnO3, inelastic neutron scattering and synchrotron based THz spectroscopy have been used to investigate the spin waves associated to the Mn order together with Ho crystal field excitations. While…
A well-known connection between the magnetic susceptibility and the effective exchange parameter is analyzed. It is shown that all current computational schemes use a long-wave approximation which is suitable only for localized moments…
The usual starting point for understanding magnons in cuprate antiferromagnets such as La$_2$CuO$_4$ is a spin model incorporating cyclic exchange, which descends from a one-band Hubbard model, and has parameters taken from fits based on…
Spin dynamics of the square lattice Heisenberg antiferromagnet, \BaMnGeO, is studied by a combination of bulk measurements, neutron diffraction, and inelastic neutron scattering techniques. Easy plane type antiferromagnetic order is…
Spin-1/2 Heisenberg antiferromagnets Cs$_2$CuCl$_4$ and Cs$_2$CuBr$_4$ with distorted triangular-lattice structures are studied by means of electron spin resonance spectroscopy in magnetic fields up to the saturation field and above. In the…
Here we report a study of the spin dynamics in the ferromagnetic chain compound $Li_{2}CuO_{2}$. Inelastic neutron scattering measurements allow for the spin Hamiltonian to be determined using a $J_{1}-J_{2}$ $XXZ$-Heisenberg spin chain…
With a variational three--body calculation we study the role of the interplay between the onsite Coulomb, Hund's rule, and superexchange interactions on the spinwave excitation spectrum of itinerant ferromagnets. We show that correlations…
This study examines the magnetic interactions between spatially-variable manganese and chromium trimers substituted into a graphene superlattice. Using density functional theory, we calculate the electronic band structure and magnetic…
The high-temperature ferromagnet MnBi continues to receive attention as a candidate to replace rare-earth-containing permanent magnets in applications above room temperature. This is due to a high Curie temperature, large magnetic moments,…
Inelastic neutron scattering (INS) provides direct insights into microscopic magnetic interactions in crystalline materials, making it a valuable experimental technique in condensed matter physics and materials science. These interactions…
Spin-wave excitations are fundamental to understanding the behavior of magnetic materials and hold promise for future information and communication technologies. Yet, modeling these accurately in transition-metal compounds remains…
Using the Lanczos method in linear chains we study the ground state of the double exchange model including an antiferromagnetic super-exchange in the low concentration limit. We find that this ground state is always inhomogeneous, containig…
We study a two-dimensional effective orbital superexchange model derived for strongly correlated e_g electrons coupled to t_{2g} core spins in layered manganites. One finds that the ferromagnetic and antiferromagnetic correlations closely…
We study the possibility of nanoscale phase separation in manganites in the framework of the double exchange model. The homogeneous canted state of this model is proved to be unstable toward the formation of small ferromagnetic droplets…
We present diffraction data on a single-layered manganite La(0.42)Sr(1.58)MnO4 with hole doping (x>0.5). Overdoped La(0.42)Sr(1.58)MnO4 exhibits a complex ordering of charges, orbitals and spins. Single crystal neutron diffraction…