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Variation of charge/orbital ordering in layered manganites Pr1-xCa1+xMnO4 investigated by transmission electron microscopy

X. Z. Yu·R. Mathieu·T. Arima·Y. Kaneko·J. P. He·M. Uchida·T. Asaka·T. Nagai·K. Kimoto·A. Asamitsu·Y. Matsui·Y. Tokura
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Abstract

Structural features of the charge/orbital ordering (CO/OO) in single-layered manganites Pr1-xCa1+xMnO4 have been investigated systematically by transmission electron microscopy. Analyses of electron diffraction patterns as well as dark-field images have revealed that the CO/OO shows a striking asymmetric behavior as the hole doping x deviates from x = 0.5. The modulation wavenumber linearly decreases with increasing x in the over-hole-doped (x > 0.5) crystals, while much less dependent on x in the under-hole-doped (x < 0.5) crystals. A temperature-induced incommensurate-commensurate crossover is observed in 0.35 < x < 0.5 and x = 0.65. The correlation length of CO/OO in x = 0.3 was proven to become shorter than that in x > 0.3.

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X. Z. Yu, R. Mathieu, T. Arima, Y. Kaneko, J. P. He, M. Uchida, T. Asaka, T. Nagai, K. Kimoto, A. Asamitsu, Y. Matsui, Y. Tokura. 2007-03-28. Variation of charge/orbital ordering in layered manganites Pr1-xCa1+xMnO4 investigated by transmission electron microscopy. https://doi.org/10.1103/physrevb.75.174441

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