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Lamellar phase separation and dynamic competition in La0.23Ca0.77MnO3

J. Tao·D. Niebieskikwiat·M. B. Salamon·J. M. Zuo
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Abstract

We report the coexistence of lamellar charge-ordered (CO) and charge-disordered (CD) domains, and their dynamical behavior, in La0.23Ca0.77MnO3. Using high resolution transmission electron microscopy (TEM), we show that below Tcd~170K a CD-monoclinic phase forms within the established CO-orthorhombic matrix. The CD phase has a sheet-like morphology, perpendicular to the q vector of the CO superlattice (a axis of the Pnma structure). For temperatures between 64K and 130K, both the TEM and resistivity experiments show a dynamic competition between the two phases: at constant T, the CD phase slowly advances over the CO one. This slow dynamics appears to be linked to the magnetic transitions occurring in this compound, suggesting important magnetoelastic effects.

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J. Tao, D. Niebieskikwiat, M. B. Salamon, J. M. Zuo. 2004-09-27. Lamellar phase separation and dynamic competition in La0.23Ca0.77MnO3. https://doi.org/10.1103/physrevlett.94.147206

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