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arXiv · 0707.4490

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

Peter R. Stone·Jeffrey W. Beeman·Kin M. Yu·Oscar D. Dubon
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Abstract

We have synthesized Ga1-xMnxAs1-yPy and Ga1-xMnxP1-yNy 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 Ga1-xMnxP1-yNy/GaP and Ga1-xMnxAs1-yPy/GaAs thin films from in-plane to out-of-plane. This tensile-strain-induced magnetic anisotropy is reminiscent of that observed in Ga1-xMnxAs 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 Ga1-xMnxAs1-yPy 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.

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Peter R. Stone, Jeffrey W. Beeman, Kin M. Yu, Oscar D. Dubon. 2007-07-30. Tuning of ferromagnetism through anion substitution in Ga-Mn-pnictide ferromagnetic semiconductors. https://doi.org/10.1016/j.physb.2007.08.210

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