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arXiv · 1506.06891

Magnetic Excitations of Spin Nematic State in Frustrated Ferromagnetic Chain

Hiroaki Onishi
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Abstract

By exploiting density-matrix renormalization group techniques, we investigate the dynamical spin structure factor of a spin-1/2 Heisenberg chain with ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange interactions in an applied magnetic field. In a field-induced spin nematic regime, we find gapless longitudinal and gapped transverse spin excitation spectra, in accordance with quasi-long-ranged longitudinal and short-ranged transverse spin correlations, respectively. The gapless point coincides with the dominant longitudinal spin correlation, whereas the gap position exhibits a characteristic field dependence contradicting the dominant transverse spin correlation.

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Hiroaki Onishi. 2015-06-23. Magnetic Excitations of Spin Nematic State in Frustrated Ferromagnetic Chain. https://doi.org/10.7566/jpsj.84.083702

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