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arXiv · 1506.06883

Effects of magnetic anisotropy on spin dynamics of ferromagnetic frustrated chain

Hiroaki Onishi
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Abstract

By exploiting density-matrix renormalization group techniques, we investigate the spin dynamics of a spin-1/2 one-dimensional J1-J2 XXZ model with competing ferromagnetic J1 and antiferromagnetic J2 exchange couplings under applied magnetic fields. Numerical results of spin excitation spectra show that in the field-induced spin quadrupole regime, the longitudinal component has a gapless mode and the transverse component has a gapped mode irrespective of the exchange anisotropy. The excitation gap of the transverse spin excitation increases as the exchange anisotropy increases over the XY-like and Ising-like regions, demonstrating that two-magnon bound states are stabilized due to the easy-axis anisotropy.

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Hiroaki Onishi. 2015-06-23. Effects of magnetic anisotropy on spin dynamics of ferromagnetic frustrated chain. https://doi.org/10.1088/1742-6596%2F592%2F1%2F012109

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