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Influence of Quasi-Bi-Stripe Charge Order on the Resistivity and Magnetism in a Bilayer Manganite La$_{2-2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$

M. Kubota·Y. Oohara·H. Yoshizawa·H. Fujioka·K. Shimizu·K. Hirota·Y. Moritomo·Y. Endoh
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Abstract

The charge ordering in the bilayer manganite system La$_{2-2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$ with $0.30 \le x \le 0.50$ has been studied by neutron diffraction. The charge order is characterized by the propagation vector parallel to the [1 0 0] direction (MnO$_2$ direction), but the correlation length is short-ranged and extremely anisotropic, being $\sim 0.02a^{*}$ and $\sim 0.2a^{*}$ parallel and perpendicular to the modulation direction, respectively. The observed charge order can be viewed as a quasi-bi-stripe order, and accounts well for the $x$ dependence of the resistivity. The quasi-bistripe order is stable within the ferromagnetic (FM) MnO$_2$ layers in the A-type antiferromagnetic order, but is instabilized by the 3 dimensional FM order.

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M. Kubota, Y. Oohara, H. Yoshizawa, H. Fujioka, K. Shimizu, K. Hirota, Y. Moritomo, Y. Endoh. 2000-05-11. Influence of Quasi-Bi-Stripe Charge Order on the Resistivity and Magnetism in a Bilayer Manganite La$_{2-2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$. https://doi.org/10.1143/jpsj.69.1986

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