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Antiferromagnetism in CaCu$_{3}$Ti$_{4}$O$_{12}$ studied by magnetic Raman spectroscopy

A. Koitzsch·G. Blumberg·A. Gozar·B. Dennis·A. P. Ramirez·S. Trebst·Shuichi Wakimoto
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Abstract

For CaCu$_{3}$Ti$_{4}$O$_{12}$ -- an insulator that exhibits a giant dielectric response above 100 K -- Cu$^{2+}$ antiferromagnetic spin ordering has been investigated by magnetic Raman scattering and magnetization measurements. Below the Néel temperature, T$_{N} = 25$ K, magnetic excitations have been identified. Above T$_{N}$ Raman spectra reveal short-range antiferromagnetic fluctuations that increase with cooling like T$^{-1}$. No deviations from Curie-Weiss law have been observed above T$_{N}$.

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A. Koitzsch, G. Blumberg, A. Gozar, B. Dennis, A. P. Ramirez, S. Trebst, Shuichi Wakimoto. 2001-12-16. Antiferromagnetism in CaCu$_{3}$Ti$_{4}$O$_{12}$ studied by magnetic Raman spectroscopy. https://doi.org/10.1103/physrevb.65.052406

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