Dynamical spin response of electron doped Mott insulators on a triangular lattice

Bin Liu; Ying Liang

doi:10.1016/j.ssc.2011.10.032

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arXiv · 1212.5371

Dynamical spin response of electron doped Mott insulators on a triangular lattice

Bin Liu·Ying Liang

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Abstract

The spin dynamics of electron doped Mott insulators on a triangular lattice is studied based on the $t-J$ model. It is found that the particularly universal behaviors of integrated dynamical spin structure factor seen in the doped Mott insulators on a square lattice, are absent in the doped Mott insulators on a triangular lattice, indicating the presence of the normal state gap. As a result, the spin-lattice relaxation rate 1/$T_{1}$ divided by $T$ reduces with decreasing temperatures in the temperature region above 0.2$J$$\approx$50K, then follows a Curie-Weiss-like behavior at the temperature less than 50K, in qualitative agreement with experimental observations.

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Bin Liu, Ying Liang. 2012-12-21. Dynamical spin response of electron doped Mott insulators on a triangular lattice. https://doi.org/10.1016/j.ssc.2011.10.032

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