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arXiv · 1302.0157

Spin Liquid States at the vicinity of metal-insulator transition

Yi Zhou·Tai-Kai Ng
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Abstract

We study in this paper quantum spin liquid states (QSLs) at the vicinity of metal-insulator transition. Assuming that the low energy excitations in the QSLs are labeled by "spinon" occupation numbers with the same Fermi surface structure as in the corresponding metal (Fermi-liquid) side, we propose a phenomenological Landau-like low energy theory for the QSLs and show that the usual U(1) QSLs is a representative member of this class of spin liquids. Based on our effective low energy theory, an alternative picture to the Brinkman-Rice picture of Mott metal-insulator transition is proposed. The charge, spin and thermal responses of QSLs are discussed under such a phenomenology.

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Yi Zhou, Tai-Kai Ng. 2013-02-01. Spin Liquid States at the vicinity of metal-insulator transition. https://doi.org/10.1103/physrevb.88.165130

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