Ab initio investigation of FeAs/GaAs heterostructures for potential spintronic and superconducting applications

TitleAb initio investigation of FeAs/GaAs heterostructures for potential spintronic and superconducting applications
Publication TypeJournal Article
Year of Publication2012
AuthorsGriffin SM, Spaldin NA
JournalPhysical Review B
Volume85
Issue15
Start Page155126
Pagination155126
Date Published04/2012
ISSN1098-0121
KeywordsCNSI, CSC, NSF
Abstract

Ultrathin FeAs is of interest both as the active component in the recently identified pnictide superconductors and in spintronic applications at the interface between ferromagnetic Fe and semiconducting GaAs. Here we use first-principles density-functional theory to investigate the properties of FeAs/GaAs heterostructures. We find that the Fermi surface is modified from that characteristic of the pnictide superconductors by interactions between the FeAs layer and the As atoms in the GaAs layers. Regardless of the number of FeAs layers, the Fe to As ratio, or the strain state, the lowest-energy magnetic ordering is always antiferromagnetic, offering an explanation for the failure of spin injection across Fe/GaAs interfaces. However, such antiferromagnetic layers could be incorporated into heterostructures as an exchange-bias layer.

URLhttp://journals.aps.org/prb/abstract/10.1103/PhysRevB.85.155126
DOI10.1103/PhysRevB.85.155126
Grant: 
HP, CSC