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arXiv · 2211.02754

Phase diagrams of spin-$S$ Kitaev ladders

Yushao Chen·Yin-Chen He·Aaron Szasz
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Abstract

We investigate the ground states of spin-$S$ Kitaev ladders using exact analytical solutions (for $S = 1/2$), perturbation theory, and the density matrix renormalization group (DMRG) method. We find an even-odd effect: in the case of half-integer $S$, we find phases with spontaneous symmetry breaking (SSB) and symmetry-protected topological (SPT) order; for integer $S$, we find SSB and trivial paramagnetic phases. We also study the transitions between the various phases; notably, for half-integer $S$ we find a transition between two distinct SPT orders, and for integer $S$ we find unnecessary first order phase transitions within a trivial phase

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Yushao Chen, Yin-Chen He, Aaron Szasz. 2022-11-04. Phase diagrams of spin-$S$ Kitaev ladders. https://doi.org/10.1103/physrevb.108.045124

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