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Structural effect on the static spin and charge correlations in La$_{1.875}$Ba$_{0.125-x}$Sr$_{x}$CuO$_{4}$

M. Fujita·H. Goka·K. Yamada·M. Matsuda
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Abstract

We report the results of elastic neutron scattering measurements performed on 1/8-hole doped La$_{1.875}$Ba$_{0.125-x}$Sr$_{x}$CuO$_{4}$ single crystals with {\it x}=0.05, 0.06, 0.075 and 0.085. In the low-temperature less-orthorhombic (LTLO, {\it Pccn} symmetry) phase, the charge-density-wave (CDW) and spin-density-wave (SDW) wavevectors 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 (LTT, {\it P}4$_2$/{\it ncm} symmetry) phase. The coincident direction of two wavevectors suggests a close relation between CDW and SDW orders. The SDW wavevector 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 (LTO, {\it B}{\it mab} symmetry) with comparable in-plane orthorhombic distortion. These results demonstrate a correlation between the corrugated pattern of CuO$_{2}$ plane and the deviations.

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M. Fujita, H. Goka, K. Yamada, M. Matsuda. 2002-11-06. Structural effect on the static spin and charge correlations in La$_{1.875}$Ba$_{0.125-x}$Sr$_{x}$CuO$_{4}$. https://doi.org/10.1103/physrevb.66.184503

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