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Spin-Charge Separation in Two-dimensional Frustrated Quantum Magnets

A. Laeuchli·D. Poilblanc
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Abstract

The dynamics of a mobile hole in two-dimensional frustrated quantum magnets is investigated by exact diagonalization techniques. Our results provide evidence for spin-charge separation upon doping the kagome lattice, a prototype of a spin liquid. In contrast, in the checkerboard lattice, a symmetry broken Valence Bond Crystal, a small quasi-particle peak is seen for some crystal momenta, a finding interpreted as a restoration of weak holon-spinon confinement.

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A. Laeuchli, D. Poilblanc. 2004-06-16. Spin-Charge Separation in Two-dimensional Frustrated Quantum Magnets. https://doi.org/10.1103/physrevlett.92.236404

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