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Quantum Melting of Magnetic Order due to Orbital Fluctuations

Louis Felix Feiner·Andrzej M. Oles·Jan Zaanen
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Abstract

We have studied the phase diagram and excitations of the spin-orbital model derived for a three dimensional perovskite lattice, as in KCuF_3. The results demonstrate that the orbital degeneracy drastically increases quantum fluctuations and suppresses the classical long-range order near the multicritical point in the mean-field phase diagram. This generates a qualitatively new spin liquid, providing the first example of a valence bond ground state in three dimensions.

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Louis Felix Feiner, Andrzej M. Oles, Jan Zaanen. 1997-01-14. Quantum Melting of Magnetic Order due to Orbital Fluctuations. https://doi.org/10.1103/physrevlett.78.2799

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