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Z_3 Quantum Criticality in a spin-1/2 chain model

P. Lecheminant·E. Orignac
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Abstract

The stability of the magnetization $m=1/3$ plateau phase of the XXZ spin-1/2 Heisenberg chain with competing interactions is investigated upon switching on a staggered transverse magnetic field. Within a bosonization approach, it is shown that the low-energy properties of the model are described by an effective two-dimensional XY model in a three-fold symmetry-breaking field. A phase transition in the three-state Potts universality class is expected separating the $m=1/3$ plateau phase to a phase where the spins are polarized along the staggered magnetic field. The Z$_3$ critical properties of the transition are determined within the bosonization approach.

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P. Lecheminant, E. Orignac. 2004-04-27. Z_3 Quantum Criticality in a spin-1/2 chain model. https://doi.org/10.1103/physrevb.69.174409

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