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Dynamical properties of S=1 bond-alternating Heisenberg chains in transverse magnetic fields

Takahumi Suzuki·Sei-ichiro Suga
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Abstract

We calculate dynamical structure factors of the S=1 bond-alternating Heisenberg chain with a single-ion anisotropy in transverse magnetic fields, using a continued fraction method based on the Lanczos algorithm. In the Haldane-gap phase and the dimer phase, dynamical structure factors show characteristic field dependence. Possible interpretations are discussed. The numerical results are in qualitative agreement with recent results for inelastic neutron-scattering experiments on the S=1 bond-alternating Heisenberg-chain compound $\rm{Ni(C_{9}D_{24}N_{4})(NO_{2})ClO_{4}}$ and the S=1 Haldane-gap compound $\rm{Ni(C_{5}D_{14}N_{2})_{2}N_{3}(PF_{6})}$ in transverse magnetic fields.

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Takahumi Suzuki, Sei-ichiro Suga. 2005-05-09. Dynamical properties of S=1 bond-alternating Heisenberg chains in transverse magnetic fields. https://doi.org/10.1103/physrevb.72.014434

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