The effects of Zn Impurity on the Properties of Doped Cuprates in the Normal State

TL;DR

This study investigates how Zn impurities affect the magnetic and electronic properties of doped cuprates in the normal state, revealing impurity-induced local antiferromagnetism and modifications in spin excitations.

Contribution

It provides a numerical analysis of impurity effects on holon and spin dynamics in high-Tc cuprates using the t-t'-J model with Green function methods.

Findings

Doped holes tend to cluster around Zn impurities, reducing their mobility.

Zn impurities induce local antiferromagnetic correlations.

Impurities cause mixing of spin excitation components at different wave vectors.

Abstract

We study the interplay of quantum impurity, and collective spinon and holon dynamics in Zn doped high-T$_c$ cuprates in the normal state. The two-dimensional t-t$^{\prime}$-J models with one and a small amount of Zn impurity are investigated within a numerical method based on the double-time Green function theory. We study the inhomogeneities of holon density and antiferromagnetic correlation background in cases with different Zn concentrations, and obtain that doped holes tend to assemble around the Zn impurity with their mobility being reduced. Therefore a bound state of holon is formed around the nonmagnetic Zn impurity with the effect helping Zn to introduce local antiferromagnetism around itself. The incommensurate peaks we obtained in the spin structure factor indicate that Zn impurities have effects on mixing the q=($\pi$, $\pi$) and q=0 components in spin excitations.