Positron potential and wavefunction in LaFeAsO

TL;DR

This paper calculates the positron potential and wavefunction in LaFeAsO, demonstrating that positron annihilation techniques can effectively probe the material's Fermi surfaces and that positive muons localize near As atoms.

Contribution

It provides the first detailed calculations of positron wavefunctions in LaFeAsO, showing their sampling of the entire unit cell and implications for experimental probes.

Findings

Positron wavefunction samples the entire unit cell.

Positron wavefunction is largest in La layer near As.

Positrons and muons localize near As atoms in LaFeAsO.

Abstract

We report calculations of the positron potential and wavefunction in LaFeAsO. These calculations show that the positron wavefunction does sample the entire unit cell although it is largest in the interstices of the La layer adjacent to As atoms. The implication is that angular correlation of annihilation radiation (ACAR) is a viable probe of the Fermi surfaces in this material. The results also apply to positive muons, and indicate that these will be localized in the La layer adjacent to As.