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Magnetization and dimerization profiles of the cut two-leg spin ladder and spin-1 chain

P. Lecheminant·E. Orignac
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Abstract

The physical properties of the edge states of the cut two-leg spin ladder are investigated by means of the bosonization approach. By carefully treating boundary conditions, we derive the existence of spin-1/2 edge states in the spin ladder with a ferromagnetic rung exchange and for the open spin-1 Heisenberg chain. In contrast, such states are absent in the antiferromagnetic rung coupling case. The approach, based on a mapping onto decoupled semi-infinite off-critical Ising models, allows us to compute several physical quantities of interest. In particular, we determine the magnetization and dimerization profiles of the cut two-leg spin ladder and of the open biquadratic spin-1 chain in the vicinity of the SU(2)$_2$ WZNW critical point.

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P. Lecheminant, E. Orignac. 2001-11-23. Magnetization and dimerization profiles of the cut two-leg spin ladder and spin-1 chain. https://doi.org/10.1103/physrevb.65.174406

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