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arXiv · 1812.01418

Spin-lattice Coupling and Magneto-dielectricity in Ca3Mn2O7 Layered Perovskite

Pooja Sahlot·Gaurav Sharma·Vasant Sathe·Anand Mohan Awasthi
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Abstract

Dielectric study on Ca3Mn2O7 features relaxor-like segmented dynamics below the antiferromagnetic ordering. Dipolar relaxations of different origin are spectrally resolved exhibiting distinct H-field alterations. This identifies their allegiance to different magnetic sub-phases and establishes dual coupling of electrical, magnetic, and structural degrees of freedom. Further, strong spin-lattice coupling has been affirmed with Raman spectroscopy across the magnetic ordering. Short-range electrical correlations collaterally cause measurable harmonic dielectric response in the system. The \c{hi}_3^e-susceptibility signal yields genuine harmonic magneto-dielectricity, consistent with but exhibiting two orders of magnitude larger H-field effect, vis-\`a-vis that obtained in the fundamental dielectric constant {\epsilon}'.

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Pooja Sahlot, Gaurav Sharma, Vasant Sathe, Anand Mohan Awasthi. 2018-12-04. Spin-lattice Coupling and Magneto-dielectricity in Ca3Mn2O7 Layered Perovskite. https://arxiv.org/abs/1812.01418

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