Related papers: Orbitally-driven Peierls state in spinels
The layered 5d transition metal oxides like Sr2IrO4 have attracted significant interest recently due to a number of exotic and new phenomena induced by the interplay between the spin-orbit coupling, bandwidth W and on-site Coulomb…
We derive general expressions for resonant inelastic x-ray scattering (RIXS) operators for $t_{2g}$ orbital systems, which exhibit a rich array of unconventional magnetism arising from unquenched orbital moments. Within the fast collision…
Recent X-ray analysis and NMR- experiments have shown that alpha'- NaV2O5 is not a conventional spin-Peierls (SP) compound because above the transition at 33K it is in a homogeneous mixed valent (MV) state and atomic spin chains do not…
The spinel FeV2O4 is known to exhibit peculiar physical properties, which is generally ascribed to the unusual presence of two cations showing a pronounced interplay between spin, orbital and lattice degrees of freedom (Fe2+ and V3+ on the…
Contrary to previous studies that classify Na2IrO3 as a realization of the Heisenberg-Kitaev model with dominant spin-orbit coupling, we show that this system represents a highly unusual case in which the electronic structure is dominated…
Phase transition and critical properties of Ising-like spin-orbital interacting systems in 2-dimensional triangular lattice are investigated. We first show that the ground state of the system is a composite spin-orbital ferro-ordered phase.…
We review electronic transport in superconducting junctions with Sr$_2$RuO$_4$. Transport measurements provide evidence for chiral domain walls and, therefore, chiral superconductivity in superconducting Sr$_2$RuO$_4$, but so far, the…
The concept of spin-orbital entanglement on superexchange bonds in transition metal oxides is introduced and explained on several examples. It is shown that spin-orbital entanglement in superexchange models destabilizes the long-range (spin…
Matter under irradiation may enter unusual transient states, outside of its equilibrium phase diagram. One of such states is a superionic-like state, in which one sublattice of a compound liquifies, whereas another one remains solid. Here,…
A novel Ti3+-based thiospinel ZnTi2S4 is successfully synthesized via a low-temperature ion-exchange reaction. ZnTi2S4 shows a signature of metallic ground state evidenced by a contribution of conduction electrons in the heat capacity and…
Motivated by the recent indications of ferromagnetism in transition metal oxide heterostructures, we propose a possible mechanism to generate ferromagnetism for itinerant t2g systems in two spatial dimensions that does not rely on the…
Temperature-dependent x-ray diffraction of the low-dimensional spin 1/2 quantum magnet TiOCl shows that the phase transition at T_{c2} = 90 K corresponds to a lowering of the lattice symmetry. Below T_{c1} = 66 K a twofold superstructure…
We present a general theory of multiorbital spin waves in magnetically ordered metallic systems. Motivated by the itinerant magnetism of iron-based superconductors, we compare the magnetic excitations for two different scenarios: when the…
The metal-insulator and spin state transitions of CoO under high pressure are studied by using density functional theory combined with dynamical mean-field theory. Our calculations predict that the metal-insulator transition in CoO is a…
Two models for the superconducting state of Sr2RuO4 have been analyzed. In an "orbital model" the in-plane and out of-plane interactions between electrons on neighboring Ru atoms are assumed to be attractive. In spite of the single particle…
Basic mechanisms controlling orbital order and orbital fluctuations in transition metal oxides are discussed. The lattice driven classical orbital picture, e.g. like in manganites LaMnO$_3$, is contrasted to the quantum behavior of orbitals…
The Mott insulator Ca2RuO4 is a paradigmatic example among transition metal oxides, where the interplay of charge, spin, orbital, and lattice degrees of freedom leads to competing quantum phases. In this paper, we focus on and review some…
Recently, a Verwey-type transition in the mixed-valence alkali sesquioxide Cs$_4$O$_6$ was deduced from the charge ordering of molecular peroxide O$_2^{2-}$ and superoxide O$_2^-$ anions accompanied by the structural transformation and a…
We studied temperature and magnetic field dependence of magnetization, $M(T)$ and $M(B)$, on thiospinel FeCr$_{2}$S$_{4}$. We observed a step-like anomaly at $T_{OO} \sim$ 9 K for $M$($T$) attributed to an orbital order transition in…
Strong spin-orbit coupling fosters exotic electronic states such as topological insulators and superconductors, but the combination of strong spin-orbit and strong electron-electron interactions is just beginning to be understood. Central…