(La1–xSrx)(Zn1–xMnx)SbO: A novel 1111-type diluted magnetic semiconductor

Abstract

Diluted magnetic semiconductor (DMS) that combines the properties of spin and charge degrees of freedom, which has potential applications in the field of spintronic devices. In the 1990s, due to the breakthrough of low-temperature molecular beam epitaxy technology, scientists successfully synthesized III-V DMS (Ga, Mn)As, and developed some spintronics devices accordingly. However, the maximum Curie temperature of (Ga, Mn)As is only 200 K, which is still below room temperature that is required for practical applications. Searching for diluted magnetic semiconductors with higher Curie temperature and the exploring of their magnetism is still one of the focuses at present. In recent years, developed from iron-based superconductors, a series of novel magnetic semiconductors have been reported. These new DMSs have the advantages of decoupled charge and spin doping, and each concentration can be precisely controlled. In this paper, novel bulk diluted magnetic semiconductors (La_1–<i>x</i>Sr_<i>x</i>)(Zn_1–<i>x</i>Mn_<i>x</i>)SbO (<i>x</i> = 0.025, 0.050,0.075, 0.10) are successfully synthesized, with the highest <i>T</i>_c ~ 27.1 K for the doping level of <i>x</i> = 0.10. We dope Sr²⁺ and Mn²⁺ into the parent semiconductor material LaZnSbO to introduce holes and moments, respectively. The ferromagnetic ordered phase transition can be observed in the samples with various doping concentrations. A relatively large coercive field is observed to be ~ 5000 Oe from the iso-thermal magnetization measurement at 2 K. The (La_1–<i>x</i>Sr_<i>x</i>)(Zn_1–<i>x</i>Mn_<i>x</i>)SbO has the same crystal structure as the “1111-type” iron-based superconductor LaFeAsO, and the lattice parameter difference is very small. It provides a possible material choice for preparing the multifunctional heterojunction devices.