Related papers: Charge Order in NaV2O5 studied by EPR
We show that the proposed zig--zag charge--ordering model for alpha'--NaV2O5 is incompatible with a single transition that induces both charge--ordering and spin gap. We introduce a two--band model for alpha'--NaV2O5 within which the…
Neutron diffraction measurements on multiferroic LuFe2O4 show changes in the antiferromagnetic (AFM) structure characterized by wavevector q = (1/3 1/3 1/2) as a function of electric field cooling procedures. The increase of intensity from…
Measurements of the electrical and thermal conductivities, thermopower and paramagnetic susceptibility have been performed on single crystal samples of Bi1/2Sr1/2MnO3 and complemented with the X-ray powder diffraction data. A pronounced…
A possible ground state of NaV_2O_5 is proposed based on the Hartree approximation for both on-site and intersite Coulomb interactions. The results indicate that the intersite Coulomb interaction induces a zigzag type of charge…
We have used rotational anisotropic polarized Raman spectroscopy to study the symmetries, the temperature and the doping dependence of the charge ordered state in metallic $(Sr_{1-x}La_{x})_{3}Ir_{2}O_{7}$. Although the Raman probe size is…
We study the extended Hubbard model with both on-site and nearest neighbor Coulomb repulsion ($U$ and $V$, respectively) in the Dynamical Mean Field theory. At quarter filling, the model shows a transition to a charge ordered phase with…
The I-Mn-V antiferromagnet, NaMnBi, develops a very large positive magnetoresistance (MR) up to 10,000% at 2 K and 9 T in crystals showing a semiconductor-to-metal transition (SMT). In the absence of an SMT, a modest (20%) MR is achieved.…
Quantum Monte Carlo and density-matrix renormalization group methods are used to study the coupled spin-pseudospin Hamiltonian in one-dimension (1D) that models the charge-ordering instability of the anisotropic Hubbard ladder at quarter…
Observation of charge ordering in single crystalline and bulk polycrystalline systems of various rare-earth based manganites is well documented. However, there is hardly any manifestation of the same when the grain size is reduced to…
The magnetic and transport properties are systematically studied on the single crystal $Na_{0.55}CoO_2$ with charge ordering and divergency in resistivity below 50 K. A long-range ferromagnetic ordering is observed in susceptibility below…
First, second and third nearest neighbor pair mixing potentials for equiatomic FePt alloys were calculated from first principles by the Connolly-Williams method within the canonical cluster expansion formalism. Using the mixing potentials…
The temperature dependence of charge order in Fe2OBO3 was investigated by resistivity and differential scanning calorimetry measurements, Mossbauer spectroscopy, and synchrotron x-ray scattering, revealing an intermediate phase between room…
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…
Data taken by various kinds of methods including NMR/NQR and neutron scattering are presented for NaxCoO2, in particular, for Na0.5CoO2. Attentions have also been paid to the x dependence of the electronic nature. The pseudo-gap-like…
Using one- and two-dimensional NMR spectroscopy applied to $^{13}$C spin-labeled (TMTTF)$_2$AsF$_6$ and (TMTTF)$_2$PF$_6$, we demonstrate the existence of an intermediate charge-ordered phase in the TMTTF family of charge-transfer salts. At…
We present a scenario for the peculiar coexistence of charge fluctuations observed in quasi-2D 1/4-filled organic conductors $\theta$-(BEDT-TTF)$_2X$ in the quantum critical regime where the charge ordering is suppressed down to zero…
We present the results of a systematic x-ray scattering study of the charge and orbital ordering in the manganite series Pr$_{1-x}$Ca$_x$MnO$_3$ with $x$=0.25, 0.4 and 0.5. The temperature dependence of the scattering at the charge and…
The specific heat, magnetic susceptibility and ESR signals of a Na-deficient vanadate Na_xV_2O_5 (x=1.00 - 0.90) were studied in the temperature range 0.07 - 10 K, well below the transition point to a spin-gap state. The contribution of…
Co and Na NMR are used to probe the local susceptibility and charge state of the two Co sites of the Na-ordered orthorhombic Na0.5CoO2. Above T_N=86K, both sites display a similar T-dependence of the spin shift, suggesting that there is no…
The temperature dependence of the integrated optical conductivity I(T) reflects the changes of the kinetic energy as spin and charge correlations develop. It provides a unique way to explore experimentally the kinetic properties of strongly…