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arXiv · 0711.0623

Alternating Heisenberg Spin-1/2 Chains in a Transverse Magnetic Field

Saeed Mahdavifar·Alireza Akbari
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Abstract

The ground state phase diagram of the alternating spin-1/2 chains with anisotropic ferromagnetic coupling under the influence of a symmetry breaking transverse magnetic field is studied. We have used the exact diagonalization technique. In the limit where the antiferromagnetic coupling is dominant, we have identified two Ising-type quantum phase transitions. We have calculated two critical fields $h_{c_{1}}$ and $h_{c_{2}}$, corresponding to the transition between different magnetic phases of the system. It is found that the intermediate state ($h_{c_{1}}<h<h_{c_{2}}$) is gapful, describing the stripe-antiferromagnetic phase.

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Saeed Mahdavifar, Alireza Akbari. 2007-11-05. Alternating Heisenberg Spin-1/2 Chains in a Transverse Magnetic Field. https://doi.org/10.1143/jpsj.77.024710

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