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Symmetry Origin of the Phase Transitions and Phase Separation in Manganites at Low Doping

Fan Zhong·Z. D. Wang
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Abstract

We analyze the symmetry changes of the paramagnetic to the A-type antiferromagnetic and to the ferromagnetic phase transitions in undoped and moderately doped LaMnO$_3$, respectively. We show that in the orthorhombic-distorted perovskite manganites the phase separation at low doping is associated with the noncollinear nature of the magnetic orders permitted by symmetry. A simple model for the competition between the two phase transitions is put forward within the framework of Landau theory of phase transitions.

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Fan Zhong, Z. D. Wang. 1999-10-27. Symmetry Origin of the Phase Transitions and Phase Separation in Manganites at Low Doping. https://doi.org/10.1103/physrevb.60.11883

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