New Diluted Ferromagnetic Semiconductor isostructural to 122 type iron pnictide superconductor with TC up to 180 K

TL;DR

This paper reports the synthesis of a new diluted ferromagnetic semiconductor, (Ba,K)(Zn,Mn)2As2, with a record high Curie temperature of 180K, isostructural to 122-type iron pnictide superconductors, promising for spintronics applications.

Contribution

The study introduces a novel bulk diluted ferromagnetic semiconductor with high Tc, combining spin and charge doping in a 122 structure, expanding materials for spintronics.

Findings

Achieved ferromagnetic order with Tc up to 180K.

Synthesized bulk samples with specific doping levels.

Shared crystal structure with other functional Ba-based compounds.

Abstract

Diluted magnetic semiconductors (DMS) have received much attention due to its potential applications to spintronics devices. A prototypical system (Ga,Mn)As has been widely studied since 1990s. The simultaneous spin and charge doping via hetero-valence (Ga3+,Mn2+) substitution, however, resulted in severely limited solubility without availability of bulk specimens. Previously we synthesized a new diluted ferromagnetic semiconductor of bulk Li(Zn,Mn)As with Tc up to 50K, where isovalent (Zn,Mn) spin doping was separated from charge control via Li concentrations. Here we report the synthesis of a new diluted ferromagnetic semiconductor (Ba1-xKx)(Zn1-yMny)2As2, isostructural to iron 122 system, where holes are doped via (Ba2+, K1+), while spins via (Zn2+,Mn2+) substitutions. Bulk samples with x=0.1-0.3 and y=0.05-0.15 exhibit ferromagnetic order with TC up to 180K, comparable to that of record high Tc for Ga(MnAs), significantly enhanced than Li(Zn,Mn)As. Moreover the (Ba,K)(Zn,Mn)2As2 shares the same 122 crystal structure with semiconducting BaZn2As2, antiferromagnetic BaMn2As2, and superconducting (Ba,K)Fe2As2, which makes them promising to the development of multilayer functional devices.