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Bandwidth-disorder phase diagram of half doped layered manganites

R. Mathieu·M. Uchida·Y. Kaneko·J. P. He·X. Z. Yu·R. Kumai·T. Arima·Y. Tomioka·A. Asamitsu·Y. Matsui·Y. Tokura
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Abstract

Phase diagrams in the plane of $r_A$ (the average ionic radius, related to one-electron bandwidth $W$) and $σ^2$ (the ionic radius variance, measuring the quenched disorder), or ``bandwidth-disorder phase diagrams'', have been established for perovskite manganites, with three-dimensional (3$D$) Mn-O network. Here we establish the intrinsic bandwidth-disorder phase diagram of half-doped layered manganites with the two-dimensional (2$D$) Mn-O network, examining in detail the ``mother state'' of the colossal magnetoresistance (CMR) phenomenon in crystals without ferromagnetic instability. The consequences of the reduced dimensionality, from 3$D$ to 2$D$, on the order-disorder phenomena in the charge-orbital sectors are also highlighted.

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R. Mathieu, M. Uchida, Y. Kaneko, J. P. He, X. Z. Yu, R. Kumai, T. Arima, Y. Tomioka, A. Asamitsu, Y. Matsui, Y. Tokura. 2006-07-05. Bandwidth-disorder phase diagram of half doped layered manganites. https://doi.org/10.1103/physrevb.74.020404

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