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arXiv · 1305.6486

Emergence of ferromagnetism and Jahn-Teller distortion in low Cr-substituted LaMnO3

A. Y. Ramos·H. C. N. Tolentino·O. Bunau·Y. Joly·S. Grenier·R. A. Souza·N. M. Souza-Neto·F. Baudelet·F. Wilhelm·A. Rogalev·O. Proux·A. Caneiro
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Abstract

The emergence of a ferromagnetic component in $LaMnO_{3}$ with low Cr-for-Mn substitution has been studied by x-ray absorption spectroscopy and x-ray magnetic circular dichroism at the Mn and Cr K edges. The local magnetic moment strength for the Mn and Cr are proportional to each other and follows the macroscopic magnetization. The net ferromagnetic components of $Cr^{3+}$ and $Mn^{3+}$ are found antiferromagnetically coupled. Unlike hole doping by La site substitution, the inclusion of $Cr^{3+}$ ions up to x = 0.15 does not decrease the Jahn-Teller (JT) distortion and consequently does not significantly affect the orbital ordering. This demonstrates that the emergence of the ferromagnetism is not related to JT weakening and likely arises from a complex orbital mixing.

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A. Y. Ramos, H. C. N. Tolentino, O. Bunau, Y. Joly, S. Grenier, R. A. Souza, N. M. Souza-Neto, F. Baudelet, F. Wilhelm, A. Rogalev, O. Proux, A. Caneiro. 2013-05-28. Emergence of ferromagnetism and Jahn-Teller distortion in low Cr-substituted LaMnO3. https://doi.org/10.1103/physrevb.87.220404

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