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arXiv · 1301.5208

Different roles of Zn$^{2+}$ and Li$^{+}$ impurities in the CuO$_2$ plane in undoped cuprate compounds

Jia-Wei Mei
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Abstract

A planar Mott insulator with easy plane N\'eel order can be mapped onto a Gutzwiller-projected spin Hall state. The in-plane substitution of Zn$^{2+}$ and Li$^{+}$ for Cu$^{2+}$ brings zero modes around the spin vacancy. The Gutzwiller projection precludes single particle excitations, however, preserves the zero modes which have a local spin moment for Zn$^{2+}$ and a local charged hole for Li$^{+}$, respectively. While the local spin moment for Zn$^{2+}$ is screened by the long-range spin correlations, the active charge degree of freedom for Li$^{+}$ impurity twists the spin background with long ranged disturbances. This proposal explains the very different roles of the Zn$^{2+}$ and Li$^{+}$ impurities on the magnetic perturbations in the CuO$_2$ plane in the undoped cuprate compounds.

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Jia-Wei Mei. 2013-01-22. Different roles of Zn$^{2+}$ and Li$^{+}$ impurities in the CuO$_2$ plane in undoped cuprate compounds. https://arxiv.org/abs/1301.5208

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