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arXiv · 1811.00404

Spin-lattice coupling mediated giant magnetodielectricity across the spin reorientation in Ca2FeCoO5

Gaurav Sharma·Shekhar Tyagi·V. R. Reddy·A. M. Awasthi·R. J. Choudhary·A. K. Sinha·Vasant Sathe
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Abstract

The structural, phonon, magnetic, dielectric, and magneto dielectric responses of the pure bulk Brownmillerite compound Ca2FeCoO5 are reported. This compound showed giant magneto dielectric response (10%-24%) induced by strong spin-lattice coupling across its spin reorientation transition (150-250 K). The role of two Debye temperatures pertaining to differently coordinated sites in the dielectric relaxations is established. The positive giant magneto-dielectricity is shown to be a direct consequence of the modulations in the lattice degrees of freedom through applied external field across the spin reorientation transition. Our study illustrates novel control of magneto-dielectricity by tuning the spin reorientation transition in a material that possess strong spin lattice coupling.

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Gaurav Sharma, Shekhar Tyagi, V. R. Reddy, A. M. Awasthi, R. J. Choudhary, A. K. Sinha, Vasant Sathe. 2018-11-01. Spin-lattice coupling mediated giant magnetodielectricity across the spin reorientation in Ca2FeCoO5. https://doi.org/10.1103/physrevb.99.024436

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