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arXiv:1902.05169 · Journal of the Physical Society of Japan

Quantized ΔS = 2 Excitation Spectra by Confinement in an S = 1 Spin Chain

Takafumi Suzuki, Sei-ichiro Suga

Published Apr 10, 2019• 1 citation
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Abstract

We calculate the dynamical spin-structure factor of the $S=1$ Ising spin chain with negative single-ion anisotropy in magnetic fields using the infinite time-evolving-block-decimation algorithm. We show that when a transverse magnetic field is applied, both the $ΔS=2$ excitation continuum and one-magnon mode appear in the low-lying excitation. When a longitudinal magnetic field is further applied, the excitation continuum changes into quantized excitation spectra. The quantized $ΔS=2$ excitation spectra originate from the confinement of two domain walls, each of which carries $ΔS=1$. The quantized excitation energies are explained by the negative zeros in the Airy function.

DOI
10.7566/jpsj.88.053702

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