J. Phys. Soc. Jpn. 29, pp. 1179-1193 (1970) [15 Pages]
FULL PAPERS

Magnetic Resonance of CoCr2O4 and MnCr2O4

+ Affiliations
1Japan Atomic Energy Research Institute Department of Physics, Faculty of Science, Osaka University Institute for Solid State Physics, University of Tokyo

Magnetic resonance of single crystals of CoCr 2 O 4 and MnCr 2 O 4 was studied below the Curie point ( T C ) at various microwave frequencies. In CoCr 2 O 4 , cancellation of angular momenta was discovered at 82.5°K ( T J ). Anomalies were also detected at 24.5°K ( T S ), above which satellite reflections are not observed in neutron diffraction, and to 10.5°K ( T I ), below which a deviation from proper conical spin structure is expected to appear due to the local instability. At higher temperatures, the resonance frequency, ω, dose not depend linearly on the external field, H . The magnitude of molecular field coefficient was estimated to be 2.8∼3.5×10 4 gram from the ω- H relationship assuming a collinear ferrimagnetic structure, which agrees with the value derived from the paramagnetic Curie point. In MnCr 2 O 4 , the anomalies corresponding to T I and T J were not found. Resonance behavior between T S (18°K) and T C is understood as that of a simple ferrimagnet.

©1970 The Physical Society of Japan

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