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Magnetic anisotropy of BaCu2Si2O7: theory and antiferromagnetic resonance

R. Hayn·V. A. Pashchenko·A. Stepanov·T. Masuda·K. Uchinokura
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Abstract

Antiferromagnetic resonance (AFMR) of BaCu2Si2O7 and a microscopic theory of the magnetic anisotropy of spin 1/2 chain compounds with folded CuO3 geometry being in good agreement with the available data are presented. The AFMR studies at 4.2 K show the existence of two gaps (40 and 76 GHz) at zero magnetic field and of two spin re-orientation transitions for H||c. The microscopic origin of the two gaps is shown to be Hund's rule coupling which leads to a "residual anisotropy" beyond the compensation of the Dzyaloshinskii-Moriya term by the symmetric anisotropy which would be valid without Hund's coupling.

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R. Hayn, V. A. Pashchenko, A. Stepanov, T. Masuda, K. Uchinokura. 2002-06-10. Magnetic anisotropy of BaCu2Si2O7: theory and antiferromagnetic resonance. https://doi.org/10.1103/physrevb.66.184414

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