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Stretched exponential behavior in remanent lattice striction of a (La,Pr)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$ bilayer manganite single crystal

M. Matsukawa·M. Chiba·R. Suryanarayanan·M. Apostu·A. Revcolevschi·S. Nimori·N. Kobayashi
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Abstract

We have investigated the time dependence of remanent magnetostriction in a (La,Pr)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$ single crystal, in order to examine the slow dynamics of lattice distortion in bilayered manganites. A competition between double exchange and Jahn-Teller type orbital-lattice interactions results in the observed lattice profile following a stretched exponential function. This finding suggests that spatial growth of the local lattice distortions coupled with e$_{g}$-electron orbital strongly correlates with the appearance of the field-induced CMR effect.

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M. Matsukawa, M. Chiba, R. Suryanarayanan, M. Apostu, A. Revcolevschi, S. Nimori, N. Kobayashi. 2004-07-02. Stretched exponential behavior in remanent lattice striction of a (La,Pr)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$ bilayer manganite single crystal. https://doi.org/10.1103/physrevb.70.132402

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