Effects of the crystal structure on the ferromagnetic correlations in ZnO with magnetic impurities

TL;DR

This study investigates how different crystal structures of (Zn,Mn)O influence ferromagnetic correlations using quantum Monte Carlo simulations, revealing structure-dependent magnetic behaviors crucial for spintronic applications.

Contribution

It demonstrates the significant impact of crystal structure on ferromagnetic correlations in (Zn,Mn)O, highlighting the role of impurity bound states and carrier type in magnetic interactions.

Findings

FM correlations are extended in p-type wurtzite and zincblende structures.

No FM correlations are observed in rocksalt structure.

N-type ZnO with magnetic impurities does not exhibit FM correlations.

Abstract

We study the ferromagnetism in the compound (Zn,Mn)O within the Haldane-Anderson impurity model by using the quantum Monte Carlo technique and the tight-binding approximation for determining the host band-structure and the impurity-host hybridization. This computational approach allows us to determine how the host crystal structure influences the impurity bound state, which plays an important role in the development of the ferromagnetic (FM) correlations between the impurities. We find that the FM correlations are strongly influenced by the crystal structure. In particular, in p-type (Zn,Mn)O, we observe the development of FM correlations with an extended range at low temperatures for wurtzite and zincblende crystal structures. However, for the rocksalt structure no FM correlations are observed between the impurities. In addition, in n-type ZnO with magnetic impurities, the impurity bound state and FM correlations are not found.