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arXiv · 0710.3978

Dielectric anomaly at T_N in LaMnO3

Parthasarathi Mondal·Dipten Bhattacharya·Pranab Choudhury·Prabhat Mandal
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Abstract

We observe a distinct anomaly in dielectric permittivity (epsilon') as well as relaxation time (tao_0) versus temperature (T) pattern at the antiferromagnetic transition point (T_N) in single crystal of LaMnO3. The equivalent circuit analysis of the impedance spectra across T_N reveals clear anomaly in the capacitive component C_0 at T_N. Since no structural transition takes place across T_N, the anomaly in tao_0 and C_0 at T_N possibly signifies multiferroicity stemming from coupling between orbital and spin order in LaMnO3.

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Parthasarathi Mondal, Dipten Bhattacharya, Pranab Choudhury, Prabhat Mandal. 2007-10-22. Dielectric anomaly at T_N in LaMnO3. https://doi.org/10.1103/physrevb.76.172403

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