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arXiv · 1703.10392

Dynamics of the lattice and spins in the phase-separated manganite (Eu$_{1-x}$Gd$_{x}$)$_{0.6}$Sr$_{0.4}$MnO$_3$

Haruka Taniguchi·Daichi Kimura·Michiaki Matsukawa·Tasuku Inomata·Satoru Kobayashi·Shigeki Nimori·Ramanathaan Suryanarayanan
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Abstract

We investigated slow relaxations of the magnetostriction and residual magnetostriction of the phase-separated system (Eu$_{1-x}$Gd$_{x}$)$_{0.6}$Sr$_{0.4}$MnO$_3$, in which the metamagnetic transition from a paramagnetic insulating state to a ferromagnetic metallic state is accompanied by a lattice shrinkage. The relaxations are well fitted by a stretched exponential function, suggesting the strong frustraction between the double exchange interaction and Jahn-Teller effect. We have revealed that the Gd substitution suppresses the frozen phase-separated phase at low temperatures and stabilizes the paramagnetic insulating state in the dynamic phase-separated phase at intermediate temperatures. The former origin would be the randomness effect and the latter would be the suppression of the double exchange interaction.

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Haruka Taniguchi, Daichi Kimura, Michiaki Matsukawa, Tasuku Inomata, Satoru Kobayashi, Shigeki Nimori, Ramanathaan Suryanarayanan. 2017-03-30. Dynamics of the lattice and spins in the phase-separated manganite (Eu$_{1-x}$Gd$_{x}$)$_{0.6}$Sr$_{0.4}$MnO$_3$. https://doi.org/10.1016/j.jmmm.2017.02.039

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