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arXiv · 0706.2477

Spin-orbital entanglement near quantum phase transitions

Andrzej M. Oles·Peter Horsch·Giniyat Khaliullin
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Abstract

Spin-orbital entanglement in the ground state of a one-dimensional SU(2)$\otimes$SU(2) spin-orbital model is analyzed using exact diagonalization of finite chains. For $S=1/2$ spins and $T=1/2$ pseudospins one finds that the quantum entanglement is similar at the SU(4) symmetry point and in the spin-orbital valence bond state. We also show that quantum transitions in spin-orbital models turn out to be continuous under certain circumstances, in constrast to the discontinuous transitions in spin models with SU(2) symmetry.

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Andrzej M. Oles, Peter Horsch, Giniyat Khaliullin. 2007-06-17. Spin-orbital entanglement near quantum phase transitions. https://doi.org/10.1002/pssb.200674619

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