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arXiv · 1903.05995

Interplay of Spin, Lattice, and Charge Degrees of Freedom in Ca3Mn2O7

Pooja Sahlot·A. K. Sinha·A. M. Awasthi
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Abstract

From low-temperature Synchrotron X-ray diffraction, a precise thermal characterization of octahedral distortions in single phase Ruddlesden-Popper Ca3Mn2O7 is performed. Highly sensitive close-steps temperature dependences of Mn-O-Mn bond angles connecting MnO6 octahedra clearly reveal signature of the spin-ordering in the system. Spin-lattice coupling is thus established via the structural distortions responsible for evolution of the magnetic state. Further, temperature anomalies observed here in volume and polarization-measure of the unit cell highlight the interplay between spin, lattice and charge degrees of freedom. Dipole-relaxation characteristics examined under applied magnetic field consistently corroborate the concurrent magnetic and structural changes, in terms of genuine and intrinsic magneto-dielectricity.

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Pooja Sahlot, A. K. Sinha, A. M. Awasthi. 2019-03-14. Interplay of Spin, Lattice, and Charge Degrees of Freedom in Ca3Mn2O7. https://doi.org/10.1111/jace.17013

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