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arXiv · 2308.09651

Pressure-induced softening in bulk modulus due to magneto-elastic coupling in Nd$_2$CoFeO$_6$ double Perovskite

Bidisha Mukherjee·Mrinmay Sahu·Debabrata Samanta·Bishnupada Ghosh·Boby Joseph·Goutam Dev Mukherjee
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Abstract

Double perovskite oxide materials have garnered tremendous interest due to their strong spin-lattice-charge coupling. Interesting in their own right, rare-earth-based DPOs have yet to be subjected to high-pressure studies. In this paper, we have investigated the structural response of Nd$_2$CoFeO$_6$ to pressure by XRD and Raman spectroscopic measurements. From XRD data, we have observed pressure-induced structural transition from the orthorhombic phase to the monoclinic phase at about 13.8~\si{\giga\pascal}. An anomalous increase in compressibility at a much lower pressure($\sim$1.1~\si{\giga\pascal}) is seen where no structural transition occurs. At about the same pressure, a sudden drop in the slope of Raman modes is observed. Further investigation at low temperatures reveals that the B$_g$ Raman mode is strongly affected by magnetic interactions. Additional high-pressure Raman experiments with the application of a magnetic field indicated that the mentioned anomaly around 1.1~\si{\giga\pascal} can be explained by a high-spin to low-spin transition of Co$^{3+}$.

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Bidisha Mukherjee, Mrinmay Sahu, Debabrata Samanta, Bishnupada Ghosh, Boby Joseph, Goutam Dev Mukherjee. 2023-08-18. Pressure-induced softening in bulk modulus due to magneto-elastic coupling in Nd$_2$CoFeO$_6$ double Perovskite. https://arxiv.org/abs/2308.09651

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