Related papers: Orbital order in ZnV$_2$O$_4$
We present first principles calculations of the magnetic and orbital properties of Ba$_2$NaOsO$_6$ (BNOO), a 5$d^1$ Mott insulator with strong spin orbit coupling (SOC) in its low temperature emergent quantum phases. Our computational…
The quasi 2-d spin 1/2 materials CaV_nO_2n+1 (n=2,3,4) are often treated as systems in which quantum effects play a dominant role: CaV_2O_5 has a spin gap and is thought to be a spin ladder; CaV_3O_7 has unusual long-range magnetic order…
We present an analytical model of orbital ordering in vanadium spinel MnV2O4. The model is based on recent first-principles calculation indicating a strong trigonal distortion at the vanadium sites of this compound [Phys. Rev. Lett. 102,…
We examine magnon and orbiton behavior in localized O$_2$ anti-bonding molecular $\pi^*$ orbitals using an effective Kugel-Khomskii Hamiltonian derived from a two band Hubbard model with hopping parameters taken from {\em ab initio} density…
The electronic structure of the doped manganites Pr$_{1-x}$Ca$_x$MnO$_3$ was calculated by the LSDA+U method which takes into account the local Coulomb interaction between d-electrons of transition metal ions. In contrast to the standard…
We have investigated electronic structures of antiferromagnetic YBaCo_2O_5 using the local spin-density approximation (LSDA) + U method. The charge and orbital ordered insulating ground state is correctly obtained with the strong on-site…
The electronic structure and magnetism in the sodium nickelate NaNiO_2 in the low-temperature phase is studied from density-functional calculations using the linear muffin-tin orbitals method. An antiferromagnetic solution with a magnetic…
A novel general method of describing the spin-lattice interactions in magnetic solids was proposed in terms of first principles calculations. The spin exchange and Dzyaloshinskii-Moriya interactions as well as their derivatives with respect…
Dilution effects on the long-range ordered state of the doubly degenerate $e_g$ orbital are investigated. Quenched impurities without the orbital degree of freedom are introduced in the orbital model where the long-range order is realized…
The model developed for LaMnO$_3$ addresses the spin-orbital order by superexchange and Jahn-Teller orbital interactions in the cubic (perovskite) symmetry up to now whereas real crystal structure is strongly deformed. We identify and…
Crystal and magnetic structures of the high-pressure stabilized perovskite phase of TlMnO3 have been studied by neutron powder diffraction. The crystal structure involves two types of primary structural distortions: a+b-b-octahedral tilting…
The effect of the spin-orbit coupling on the ground state properties of the square-lattice three-band Hubbard model with a single electron per site is studied by a generalized Hartree-Fock approximation. We calculate the full phase diagram…
The quasi-two-dimensional material Sr$_2$RuO$_4$ is a paradigmatic example of a correlated system that exhibits unconventional superconductivity and intriguing magnetic properties. The interplay between these two effects and the resulting…
Structure with orbital degeneracy is unstable toward spontaneous distortion. Such orbital correlation usually has a much higher energy scale than spins, and therefore, magnetic transition takes place at a much lower temperature, almost…
We have observed the orbital ordering in the ferromagnetic Mott-insulator Lu2V2O7 by the polarized neutron diffraction technique. The orbital ordering pattern determined from the observed magnetic form factors can be explained in terms of a…
Motivated by the quasi-1D antiferromagnet CaV$_2$O$_4$, we explore spin-orbital systems in which the spin modes are gapped but orbitals are near a macroscopically degenerate classical transition. Within a simplified model we show that…
Spectra of one-electron and collective excitations in narrow-band ferromagnets with unquenched orbital moments are calculated in various theoretical models. The interaction of spin and orbital excitations with conduction electrons results…
We present a mean-field theory of charge, orbital, and spin ordering in manganites at 50% and 0% dopings by considering Jahn-Teller interaction, nearest-neighbor repulsion, and no single-site double occupancy. For spinless fermions, we show…
The electronic and magnetic properties of monoclinic double perovskite Sr$_2$CeIrO$_6$ were examined based on both experiments and first-principles density functional theory calculations. From the calculations we conclude that…
We describe an ab initio theory of finite temperature magnetism in strongly-correlated electron systems. The formalism is based on spin density functional theory, with a self-interaction corrected local spin density approximation…