Related papers: Charge order, orbital order, and electron localiza…
We present evidence that the metal-insulator transition (MIT) in a tensile strained NdNiO3 (NNO) film is facilitated by a redistribution of electronic density and neither requires Ni charge disproportionation nor symmetry change [1, 2].…
We compute the electronic structure, spin and charge state of Fe ions, and structural phase stability of paramagnetic CaFeO$_3$ under pressure using a fully self-consistent in charge density DFT+dynamical mean-field theory method. We show…
Temperature dependences of a magnetic and an orbital Bragg reflection at the Mn L2 and L3 edges of La0.5Sr1.5MnO4 have been collected. The temperature evolution of the orbital reflection depend strongly on the x-ray energy and reflects the…
We argue that aspects of the anomalous, low temperature, spin and charge dynamics of the high temperature superconductors can be understood by studying the corresponding physics of undoped Mott insulators. Such insulators display a quantum…
The organic salt $\alpha$-(BEDT-TTF)$_2$I$_3$ is considered a model system for metal-insulator transition due to electronic charge ordering at $T_{\rm CO}=135$~K. The optical properties obtained from polarized reflection measurements above…
The quasi-one-dimensional spin ladder compounds, BaFe$_2$S$_3$ and BaFe$_2$Se$_3$, are investigated by infrared spectroscopy and density functional theory (DFT) calculations. We observe strong anisotropic electronic properties and an…
Single crystal X-ray diffraction measurements were performed on one-dimensional mixed valence vanadium bronze $\beta$-SrV$_6$O$_{15}$ in which a metal-insulator transition exists at 170 K. Above 170 K the P2$_1$/a structure with zigzag…
The interplay between unconventional superconductivity and the ordering of charge/spin density wave is one of the most vital issues in both condensed matter physics and material science. The Ti-based compound BaTi_2As_2O, which can be seen…
Charge ordering in the low-temperature monoclinic structure of iron oxoborate (Fe2OBO3) is investigated using the local spin density approximation (LSDA)+U method. While the difference between t_{2g} minority occupancies of Fe^{2+} and…
The interplay among topology, charge-density wave (CDW), and magnetism can give rise to a plethora of exotic quantum phenomena. Recently, a group of magnetic topological semimetals with tetragonal lattices and CDW order were found to…
Insulator-to-metal transition in Ca$_{2}$RuO$_{4}$ has drawn keen attention because of its sensitivity to various stimulation and its potential controllability. Here, we report a direct observation of Fermi surface, which emerges upon…
To gain insight into the mechanism of charge-ordering transitions, which conventionally are pictured as a disproportionation of an ion M as 2M$^{n+}$ $\rightarrow$ M$^{(n+1)+}$ + M$^{(n-1)+}$, we (1) review and reconsider the charge state…
Using density-functional theory calculations and experimental investigations on structural, magnetic and dielectric properties, we have elucidated a unique tetragonal ground state for MnTi2O4, a Ti^{3+} (3d^1)-ion containing spinel-oxide.…
Theoretical model for magnetic ordering in the heavy-fermion metal URu2Si2 is suggested. The 17.5K transition in this material is ascribed to formation of a spin-density wave, which develops due to a partial nesting between electron and…
In this letter we report the stress induced Mn charge-ordering process in the LiMn2O4 spinel, evidenced by the lattice strain evolutions due to the Jahn-Teller effects. In-situ neutron diffraction, reveals that the initial stage of this…
The spin-one-half Falicov-Kimball model is solved exactly on an infinite-coordination-number Bethe lattice in the thermodynamic limit. This model is a paradigm for a charge-transfer metal-insulator transition where the occupancy of…
Charge-density-wave (CDW) instability and pressure-induced superconductivity in bulk 1T-NbS2 are predicted theoretically by first-principles calculations. We reveal a CDW instability towards the formation of a stable commensurate CDW order,…
We apply ultrafast spectroscopy to establish a time-domain hierarchy between structural and electronic effects in a strongly-correlated electron system. We discuss the case of the model system VO2, a prototypical non-magnetic compound that…
The metal-insulator transition in manganites is strongly influenced by the concentration of holes present in the system. Based upon an orbitally degenerate Mott-Hubbard model we analyze two possible localization scenarios to account for…
Iron oxide is a key compound to understand the state of the deep Earth. It has been believed that previously known oxides such as FeO and Fe2O3 will be dominant at the mantle conditions. However, recent observation of FeO2 shed another…