Magnetic order in lightly doped cuprates: Coherent vs. incoherent hole quasiparticles and non-magnetic impurities

TL;DR

This paper explores how non-magnetic impurities affect magnetic order in lightly doped cuprates, showing that impurities can stabilize antiferromagnetism by disrupting hole quasiparticle coherence.

Contribution

It demonstrates that non-magnetic impurities enhance magnetic order in lightly doped cuprates by reducing hole quasiparticle coherence, supported by calculations within the t-J model.

Findings

Impurities make antiferromagnetic order more robust against doping.

Hole quasiparticle coherence is reduced by impurity scattering.

Results align with experimental observations in Zn-doped cuprates.

Abstract

We investigate magnetic properties of lightly doped antiferromagnetic Mott insulators in the presence of non-magnetic impurities. Within the framework of the t-J model we calculate the doping dependence of the antiferromagnetic order parameter using the self-consistent diagrammatic techniques. We show that in the presence of non-magnetic impurities the antiferromagnetic order is more robust against hole doping in comparison with the impurity-free host, implying that magnetic order can re-appear upon Zn doping into lightly hole-doped cuprates. We argue that this is primarily due to the loss of coherence and reduced mobility of the hole quasiparticles caused by impurity scattering. These results are consistent with experimental data on Zn-doped LaSrCuO.