Antiferromagnetism in CaCu3Ti4O12 studied by magnetic Raman spectroscopy

  • Blumberg G.
  • Dennis B.
  • Gozar A.
  • Koitzsch A.
  • Ramirez A.
  • Trebst S.
  • Wakimoto S.

For CaCu3Ti4O12—an insulator that exhibits a giant dielectric response above 100 K—Cu21 antiferromagnetic spin ordering has been investigated by magnetic Raman scattering and magnetization measurements. Below the Ne´el temperature, TN525 K, magnetic excitations have been identified. Above TN Raman spectra reveal short-range antiferromagnetic fluctuations that increase with cooling like T21. No deviations from Curie-Weiss law have been observed above TN .

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