Tuning of ferromagnetism through anion substitution in Ga–Mn–pnictide ferromagnetic semiconductors

• Published in: Physica. B, Condensed matter Vol. 401; pp. 454 - 457
• Main Authors: Stone, Peter R., Beeman, Jeffrey W., Yu, Kin M., Dubon, Oscar D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2007
• Subjects: Ferromagnetic semiconductors; Gallium manganese arsenide; Gallium manganese phosphide; Magnetic anisotropy; Metal–insulator transition; Metal–insulator transition; Ferromagnetic semiconductors; Gallium manganese arsenide; Gallium manganese phosphide; Magnetic anisotropy
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2007.08.210

We have synthesized Ga 1− x Mn x As 1− y P y and Ga 1− x Mn x P 1− y N y by the combination of ion implantation and pulsed-laser melting. We find that the incorporation of isovalent impurities with smaller atomic radii leads to a realignment of the magnetic easy axis in Ga 1− x Mn x P 1− y N y /GaP and Ga 1− x Mn x As 1− y P y /GaAs thin films from in-plane to out-of-plane. This tensile-strain-induced magnetic anisotropy is reminiscent of that observed in Ga 1− x Mn x As grown on larger lattice constant (In, Ga)As buffer layers indicating that the role of strain in determining magnetic anisotropy is fundamental to III–Mn–V materials. In addition, we observe a decrease in the ferromagnetic Curie temperature in Ga 1− x Mn x As 1− y P y with increasing y from 0 to 0.028. Such a decrease may result from localization of holes as the P/As ratio on the Group V sublattice increases.