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Spin dynamics of a one-dimensional spin-1/2 fully anisotropic Ising-like antiferromagnet in a transverse magnetic field

Asimkumar Ghosh
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Abstract

We consider the one-dimensional Ising-like fully anisotropic S=1/2 Heisenberg antiferromagnetic Hamiltonian and study the dynamics of domain wall excitations in the presence of transverse magnetic field $h_x$. We obtain dynamical spin correlation functions along the magnetic field $S^{xx}(q,ω)$ and perpendicular to it $S^{yy}(q,ω)$. It is shown that the line shapes of $S^{xx}(q,ω)$ and $S^{yy}(q,ω)$ are purely symmetric at the zone-boundary. It is observed in $S^{yy}(q,ω)$ for $π/2<q<π$ that the spectral weight moves toward low energy side with the increase of $h_x$. This model is applicable to study the spin dynamics of CsCoCl$_3$ in the presence of weak interchain interactions.

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Asimkumar Ghosh. 2001-09-20. Spin dynamics of a one-dimensional spin-1/2 fully anisotropic Ising-like antiferromagnet in a transverse magnetic field. https://doi.org/10.1088/0953-8984%2F13%2F22%2F314

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