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arXiv · 0812.4634

Quantum phase transitions in a spin-1/2 alternating Heisenberg antiferromagnetic chain under a staggered transverse magnetic field

Guang-Qiang Zhong·Shou-Shu Gong·Qing-Rong Zheng·Gang Su
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Abstract

The magnetic behaviors of a spin-1/2 alternating Heisenberg antiferromagnetic chain in a staggered transverse magnetic field is studied by means of the density-matrix renormalization group method and Jordan-Wigner transformation. Quantum phase transitions of different types are observed in the S=1 Neel and XY-like gapless phases, which result from the competitions between the staggered transverse field and magnetic orders induced by anisotropy and alternating interactions. The results are compared with the mean-field and some exactly resolved results.

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Guang-Qiang Zhong, Shou-Shu Gong, Qing-Rong Zheng, Gang Su. 2009-04-03. Quantum phase transitions in a spin-1/2 alternating Heisenberg antiferromagnetic chain under a staggered transverse magnetic field. https://doi.org/10.1016/j.physleta.2008.12.073

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