Hideto Goka

Competition between charge- and spin-density-wave order and superconductivity in La1.875Ba0.125-xSrxCuO4

We have performed a series of elastic neutron scattering measurements on 1/8-hole doped La(1.875)-Ba(0.125-x)Sr(x)CuO(4) single crystals with x = 0.05, 0.06, 0.075, and 0.085. Both charge-density-wave (CDW) and spin-density-wave orders are found to develop simultaneously below the structural transition temperature between the low-temperature orthorhombic (LTO) and low-temperature tetragonal (LTT) or low-temperature less-orthorhombic (LTLO) phases. In the ground state the CDW order is observed only in the LTT/LTLO phase and drastically degrades towards the LTO boundary. The x dependence of T(c) strongly suggests a direct effect of the CDW order on the suppression of superconductivity.

Structural effect on the static spin and charge correlations in La1.875Ba0.125-xSrxCuO4

We report the results of elastic neutron-scattering measurements performed on -hole-doped La 1 . 8 7 5 Ba 0 . 1 2 5 - x Sr x CuO 4 single crystals with x=0.05, 0.06, 0.075, and 0.085. In the low-temperature less-orthorhombic[(LTLO), Pccn symmetry] phase, the charge-density-wave (CDW) and spin-density-wave (SDW) wave vectors were found to tilt in a low-symmetric direction with one-dimensional anisotropy in the CuO 2 plane, while they were aligned along the high-symmetry axis in the low-temperature tetragonal (P4 2 /ncm symmetry) phase. The coincident direction of two wave vectors suggests a close relation between CDW and SDW orders. The SDW wave vector systematically deviates from the Cu-O bond direction in the LTLO phase upon Sr substitution and the tilt angle in the LTLO phase is smaller than that in the low-temperature orthorhombic phase (Bmab symmetry) with comparable in-plane orthorhombic distortion. These results demonstrate a correlation between the corrugated pattern of the CuO 2 plane and the deviations.

Synchrotron x-ray diffraction study of a charge stripe order in 1/8-doped La1.875Ba0.125-xSrxCuO4

Lattice distortions associated with charge stripe order in 1/8 hole-doped La

Magnetic field-effect on static spin correlation in stripe ordered phase of La2−xBaxCuO4

_{1.875}

Soft Phonons and Structural Phase Transitions in La1.875Ba0.125CuO4

Ba

Magnetic excitations in the spin-glass phase of La2−xSrxCuO4

_{0.125-x}

A comparative study on the magnetic order in hole- and electron-doped high-Tc cuprates

Sr

Effect of structural symmetry on the magnetic and superconducting properties in La1.875Ba0.125−xSrxCuO4

_{x}

Elastic constant of the vortex lattice in La1.875Ba0.065Sr0.060CuO4

CuO

Structural effect on the stability of magnetic order in La1.875Ba0.125−xSrxCuO4

_{4}