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arXiv · 1806.01434

Dynamical quadrupole structure factor of frustrated ferromagnetic chain

Hiroaki Onishi
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Abstract

We investigate the dynamical quadrupole structure factor of a spin-1/2 $J_{1}$-$J_{2}$ Heisenberg chain with competing ferromagnetic $J_{1}$ and antiferromagnetic $J_{2}$ in a magnetic field by exploiting density-matrix renormalization group techniques. In a field-induced spin nematic regime, we observe gapless excitations at $q=π$ according to quasi-long-range antiferro-quadrupole correlations. The gapless excitation mode has a quadratic form at the saturation, while it changes into a linear dispersion as the magnetization decreases.

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Hiroaki Onishi. 2018-06-04. Dynamical quadrupole structure factor of frustrated ferromagnetic chain. https://doi.org/10.1016/j.physb.2017.10.056

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