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arXiv · 0805.1112

Electronic Structure, Phonons and Dielectric Anomaly in Ferromagnetic Insulating Double Perovskite La2NiMnO6

Hena Das·Umesh V. Waghmare·T. Saha-Dasgupta·D. D. Sarma
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Abstract

Using first-principles density functional calculations, we study the electronic and magnetic properties of ferromagnetic insulating double-perovskite compound La2NiMnO6, which has been reported to exhibit interesting magnetic field sensitive dielectric anomaly as a function of temperature. Our study reveals existence of very soft infra-red active phonons that couple strongly with spins at the Ni and Mn sites through modification of the super-exchange interaction. We suggest that these modes are the origin for observed dielectric anomaly in La2NiMnO6.

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Hena Das, Umesh V. Waghmare, T. Saha-Dasgupta, D. D. Sarma. 2008-05-08. Electronic Structure, Phonons and Dielectric Anomaly in Ferromagnetic Insulating Double Perovskite La2NiMnO6. https://doi.org/10.1103/physrevlett.100.186402

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