Related papers: Microscopic examinations of Co valences and spin s…

We study ferromagnetic ordering and microscopic inhomogeneity in tensile strained LaCoO$_3$ using numerical simulations. We argue that both phenomena originate from effective superexchange interactions between atoms in the high-spin (HS)…

We report the continuous variation of the spin moment of cobalt in LaCoO3 across its temperature and pressure-induced spin transitions evidenced with K\beta emission spectra. The first thermal transition is best described by a transition to…

The doping series Eu1-xCaxCoO3-d provides a rather peculiar way to study the spin-state transition in cobalt-based complex oxides since partial substitution of Eu3+ ions by Ca2+ ions does not increase the mean valence state of cobalt but is…

Spin-state ordering - a periodic pattern of ions with different spin-state configurations along a crystal lattice - is a rare phenomenon, and its possible interrelation with other electronic degrees of freedom remains little explored. Here…

First-principles calculations show the formation of a 2D spin polarized electron (hole) gas on the Li (CoO$_2$) terminated surfaces of finite slabs down to a monolayer of LiCoO$_2$ in remarkable contrast with the bulk band structure…

Epitaxial thin films of LaCoO_{3} (E-LCO) exhibit ferromagnetic order with a transition temperature T_c = 85 K, while polycrystalline thin LaCoO_{3} films (P-LCO) remain paramagnetic. The temperature-dependent spin-state structure for both…

The electronic and magnetic states in doped perovskite cobaltites, (La, Sr)CoO_3, are studied in the numerically exact diagonalization method on Co_2O_{11} clusters. For realistic parameter values, it is shown that a high spin state and an…

Magnetic properties of Li$_x$CoO$_2$ for $x = 0.94, 0.75, 0.66$ and $0.51$ were investigated in frames of method combining Generalized Gradient Approximation with Dynamical Mean--Field Theory (GGA+DMFT). We found that a delicate interplay…

The substitutional dependence of valence and spin-state configurations of Sr(Fe$_{1-x}$Co$_x$)$_2$As$_2$ ($x =$ 0, 0.05, 0.11, 0.17, and 0.38) is investigated with near-edge x-ray absorption fine structure at the $L_{2,3}$ edges of Fe, Co,…

The Co-doped anatase TiO$_{2}$, a recently discovered room-temperature ferromagnetic insulator, has been studied by the first-principles calculations in the pseudo-potential plane-wave formalism within the local-spin-density approximation…

Three fundamentally different electronic structures for 3d electron states in LaCoO3, discussed in the current literature, have been presented. We are in favour of the localized electron atomic- like approach that yields the discrete energy…

We have carried out a comparative theoretical study of the electronic structure of the novel one-dimensional Ca$_3$CoRhO$_6$ and Ca$_3$FeRhO$_6$ systems. The insulating antiferromagnetic state for the Ca$_3$FeRhO$_6$ can be well explained…

CoO has an odd number of electrons in its unit cell, and therefore is expected to be metallic. Yet, CoO is strongly insulating owing to significant electronic correlations, thus classifying it as a Mott insulator. We investigate the…

The normal-state in-plane resistivity (\rho_{ab}) is measured in lightly Zn-doped La_{2-x}Sr_xCuO_4 (LSCO) crystals with 0.06 \leq x \leq 0.17 to systematically study the localization behavior. It is found that the localization temperature,…

We sought the origin of the metal-insulator transition in Sr2-xLaxCoO4, using electron-correlation corrected density functional calculations. Our results show that Sr2CoO4 is in an intermediate-spin (IS) state and a strong Co4+ 3d-O 2p…

\lco{} is known for its two-step spin crossover as a function of temperature. Despite efforts spanning over half a century, the origin of this phenomenon is still debated, particularly regarding how the microscopic spin states are involved…

We investigate the structural, magnetic and spin-state transitions, and magnetocaloric properties of Sr$_{2-x}$La$_x$CoNbO$_6$ ($x=$ 0--1) double perovskites. The structural transition from tetragonal to monoclinic phase at $x$ $\geqslant$…

We have studied the influence of intrinsic and extrinsic defects in the magnetic and electrical transport properties of Co-doped ZnO thin films. X ray absorption measurements show that Co substitute Zn in the ZnO structure and it is in the…

We have investigated the valence, spin, and orbital state of the Co ions in the one-dimensional cobaltate Ca3Co2O6 using x-ray absorption and x-ray magnetic circular dichroism at the Co-L2,3 edges. The Co ions at both the octahedral Co_oct…

Using \emph{ab initio} band structure and DFT+dynamical mean-field theory methods we examine the effects of electron-electron interactions on the electronic structure, magnetic state, and structural phase stability of the recently…