相关论文: Evidence for Jahn-Teller-driven metal-insulator tr…
We report a novel dielectric anomaly around the Jahn-Teller orbital order-disorder transition temperature T_JT in LaMnO_(3+delta). The transition has been characterized by resistivity (rho)versus temperature (T), calorimetry, and…
We discuss Mott insulating and metallic phases of a model with $e_g$ orbital degeneracy to understand physics of Mn perovskite compounds. Quantum Monte Carlo and Lanczos diagonalization results are discussed in this model. To reproduce…
The deviation of positions of atoms from their ideal lattice sites in crystalline solid state systems causes distortion and can lead to variation in structural [1] and functional properties [2]. Distortion in molecular systems has been…
We thoroughly analyze the divergences of the irreducible vertex functions occurring in the charge channel of the half-filled Hubbard model in close proximity to the Mott metal-insulator transition (MIT). In particular, by systematically…
Strain-regulated ferroelectric (FE) materials have long attracted significant attention due to their diverse applications. While soft-phonon theory and the (pseudo) Jahn-Teller effect have achieved considerable success in providing…
LiOsO3 is the first experimentally confirmed polar metal. Previous works suggested that the ground state of LiOsO$_3$ is just close to the critical point of metal-insulator transition. In this work the electronic state of LiOsO$_3$ is tuned…
Contradictory theoretical results for oxygen vacancies in SrTiO$_3$ (STO) were often related to the peculiar properties of STO, which is a $d^0$ transition metal oxide with mixed ionic-covalent bonding. Here, we apply, for the first time,…
At 750K, LaMnO_3 has a cooperative Jahn-Teller (JT) distortion, with Mn atoms in distorted oxygen octahedra. This lifts the degeneracy of the singly-occupied $e_g$ orbitals of the Mn$^{3+}$ ions, which then become orbitally ordered. We use…
VO2 is renowned for its electric transition from an insulating monoclinic (M1) phase characterized by V-V dimerized structures, to a metallic rutile (R) phase above 340 Kelvin. This transition is accompanied by a magnetic change: the M1…
The quest for molecular structures exhibiting strong quantum interference effects in the transport setting has long been on the forefront of chemical research. Here, we establish theoretically that the unusual geometry of spiro-conjugated…
We study the metal-insulator transition accompanied with a charge ordering in the one-dimensional (1D) t-J' model at quarter filling by the density matrix renormalization group method. In this model the nearest-neighbor hopping energy t…
We study a model for the metal-insulator (MI) transition in the rare-earth nickelates RNiO$_3$, based upon a negative charge transfer energy and coupling to a rock-salt like lattice distortion of the NiO$_6$ octahedra. Using exact…
The long-range spectral density correlations (spectral rigidities $\bar{\Delta}_3(\bar n)$ and related spectral compressibilities) of the $E\otimes (b_1+b_2)$ Jahn-Teller model are found strongly nonuniversal with respect to the Hamiltonian…
The mixed-valence perovskitelike manganites are characterized by unique interrelation of Jahn-Teller distortions, electric and magnetic properties. The Jahn-Teller distortion follows the Mn(3+)->Mn(4+) charge transfer with some delay. Its…
We report the temperature dependent mid- and near-infrared spectra of K4C60, Rb4C60 and Cs4C60. The splitting of the vibrational and electronic transitions indicates a molecular symmetry change of C604- which brings the fulleride anion from…
Vanadium sesquioxide (V2O3) is an archetypal Mott insulator in which the atomic positions and electron correlations change as temperature, pressure or doping are varied giving rise to different structural, magnetic or electronic phase…
Sr3Ir2O7 exhibits a novel Jeff=1/2 insulating state that features a splitting between Jeff=1/2 and 3/2 bands due to spin-orbit interaction. We report a metal-insulator transition in Sr3Ir2O7 via either dilute electron doping (La3+ for Sr2+)…
Based on recent experiments, we describe the Mott insulating, but undimerized state of $TiOCl$ using the local-density approximation combined with multi-orbital dynamical mean field theory (LDA+DMFT) for this $3d^{1}$ system.Good agreement…
Tin doped indium oxide (ITO) thin films are being used extensively as transparent conductors in several applications. In the present communication, we report the electrical transport in DC magnetron sputtered ITO thin films in low…
It is shown that recent experiments indicating a metal-insulator transition in 2D electron systems can be interpreted in terms of a simple model, in which the resistivity is controlled by scattering at charged hole traps located in the…