相关论文: Current-driven orbital order-disorder transition i…

The prototypical antiferroelectric PbZrO$_3$ has several unsettled questions, such as the nature of the antiferroelectric transition, possible intermediate phase and the microscopic origin of the Pbam ground state. Using first principles,…

We show that Joule heating causes current-controlled negative differential resistance (CC-NDR) in TiO2 by constructing an analytical model of the voltage-current V(I) characteristic based on polaronic transport for Ohm's Law and Newton's…

We report observation of substantial thermal relaxation in single crystal of charge ordered system Pr$_{0.63}$Ca$_{0.37}$MnO$_3$ in an applied magnetic field of H = 8T. The relaxation is observed when the temperature is scanned in presence…

Distortions of the oxygen sublattice couple to $e_g$ orbitals of Mn$^{3+}$ and drive a cooperative Jahn-Teller (orbital ordering) transition in LaMnO$_3$. A simple model for this transition is studied. Without further adjustment, the model…

Temperature dependence of the in-plane electrical resistivity, $\rho_{\rm ab}$, in various magnetic fields has been measured in the single-crystal La$_{2-x}$Ba$_x$CuO$_4$ with $x=0.08$, 0.10, 0.11 and La$_{1.6-x}$Nd$_{0.4}$Sr$_x$CuO$_4$…

Non-linear conduction in a single crystal of charge-ordered Pr$_{0.63}$Ca$_{0.37}$MnO$_{3}$ has been investigated in an applied magnetic field. In zero field, the non-linear conduction, which starts at T$<$T$_{CO}$ can give rise to a region…

Low as well as high-temperature electron and x-ray diffraction studies have been carried out on a rare-earth free B-site disordered electron-doped manganite SrMn0.875.Mo0.125O3-{\delta} in the temperature range of 83K to 637K. These studies…

Measurements of the structure of hexagonal RMnO3 (R=rare earths (Ho) and Y) for temperatures significantly above the ferroelectric transition temperature (TFE) were conducted to determine the nature of the transition. The local and long…

The tetragonal domain structure in SrTiO$_{3}$ (STO) is known to modulate the normal-state carrier density in LaAlO$_{3}$/SrTiO$_{3}$ (LAO/STO) heterostructures, among other electronic properties, but the effect of STO domains on the…

Microstructure properties, phase transitions, and charge ordering in the LuFe2O4 materials have been extensively investigated by means of transmission electron microscopy (TEM). The (001) twins as a common defect frequently appear in the…

We present the results of detailed dielectric investigations of the relaxation dynamics in DyMnO$_3$ multiferroic manganite. Strong low-frequency relaxation process near the paraelectric-ferroelectric phase transition is observed. The high…

Rare earth perovskites ($R^{3+}$M$^{3+}$O$_3$), with $e_g^1$ electronic occupation of the M $d$ states, display different types of metal-insulator transition. For manganites (M=Mn), metal-insulator transition is usually induced by the…

We develop a procedure to determine the portion of exact Hartree-Fock exchange interaction contained in a hybrid density functional to treat the range of electronic correlation governing the physics of a system as a function of a…

La3Co4Sn13 is a superconducting material with transition temperature at Tc = 2.70 K, which presents a superlattice structural transition at T* ~ 150 K, a common feature for this class of compounds. However, for this material, it is not…

Orbital ordering has recently emerged as another important state in iron based superconductors, and its role for superconductivity as well as its connection to magnetic order and orthorhombic lattice distortion are heavily debated. In order…

We present a study of the structure, the electric resistivity, the magnetic susceptibility, and the thermal expansion of La$_{1-x}$Eu$_x$CoO$_3$. LaCoO$_3$ shows a temperature-induced spin-state transition around 100 K and a metal-insulator…

Reversible topotactic transitions between oxygen-vacancy-ordered structures in transition metal oxides provide a promising strategy for active manipulation of material properties. While transformations between various oxygen-deficient…

We report the existence of a phase transition at high temperature in the 3D Kitaev candidate material, $\beta$-Li$_2$IrO$_3$. We show that the transition is bulk, intrinsic and orders a tiny magnetic moment with a spatially anisotropic…

Non-linear conduction in a charge-ordered manganese oxide Pr$_{0.63}$Ca$_{0.37}$MnO$_3$ is reported. To interpret such a feature, it is usually proposed that a breakdown of the charge or orbitally ordered state is induced by the current.…

We review the theory of second--order (ferro--)elastic phase transitions, where the order parameter consists of a certain linear combination of strain tensor components, and the accompanying soft mode is an acoustic phonon. In…