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Formation of energy gap in higher dimensional spin-orbital liquids

Shun-Qing Shen·Guang-Ming Zhang
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Abstract

A Schwinger boson mean field theory is developed for spin liquids in a symmetric spin-orbital model in higher dimensions. Spin, orbital and coupled spin-orbital operators are treated equally. We evaluate the dynamic correlation functions and collective excitations spectra. As the collective excitations have a finite energy gap, we conclude that the ground state is a spin-orbital liquid with a two-fold degeneracy, which breaks the discrete spin-orbital symmetry. Possible relevence of this spin liquid state to several realistic systems, such as CaV$_4$V$_9$ and Na$_2$Sb$_2$Ti$_2$O, are discussed.

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Shun-Qing Shen, Guang-Ming Zhang. 2001-09-13. Formation of energy gap in higher dimensional spin-orbital liquids. https://doi.org/10.1209/epl%2Fi2002-00572-5

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