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An electron paramagnetic resonance study of Pr_{0.6}Ca_{0.4}MnO_{3} across the charge ordering transition

Rajeev Gupta·Janhavi P. Joshi·S. V. Bhat·A. K. Sood·C. N. R. Rao
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Abstract

We report the first electron paramagnetic resonance studies of single crystals and powders of Pr_{0.6}Ca_{0.4}MnO_{3} in the 300-4.2 K range, covering the charge ordering transition at ~ 240 K and antiferromagnetic transition (T_N) at ~ 170 K. The asymmetry parameter for the Dysonian single crystal spectra shows anomalous increase at T_{co}. Below T_{co} the g-value increases continuously, suggesting a gradual strengthening of orbital ordering. The linewidth undergoes a sudden increase at T_{co} and continues to increase down to T_N. The intensity increases as the temperature is decreased till T_{co} due to the renormalization of magnetic susceptibility arising from the build up of ferromagnetic correlations. The value of the exchange constant, J, is estimated to be 154 K.

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Rajeev Gupta, Janhavi P. Joshi, S. V. Bhat, A. K. Sood, C. N. R. Rao. 2000-06-05. An electron paramagnetic resonance study of Pr_{0.6}Ca_{0.4}MnO_{3} across the charge ordering transition. https://doi.org/10.1088/0953-8984%2F12%2F30%2F319

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