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Register a new userMolecular beam epitaxy of the half-Heusler antiferromagnet CuMnSb
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We report growth of CuMnSb thin films by molecular beam epitaxy on InAs(001) substrates. The CuMnSb layers are compressively strained ($0.6~text{%}$) due to lattice mismatch. The thin films have a $omega$ full width half max of $7.7^{}$ according to high resolution X-ray diffraction, and a root mean square roughness of $0.14~text{nm}$ as determined by atomic force microscopy. Magnetic and electrical properties are found to be consistent with reported values from bulk samples. We find a Neel temperature of $62~text{K}$, a Curie-Weiss temperature of $-65~text{K}$ and an effective moment of $5.9~mu_{text{B}}/text{f.u.}$. Transport measurements confirm the antiferromagetic transition and show a residual resistivity at $4~text{K}$ of $35~muOmegacdot text{cm}$.
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We present a detailed study of the growth of the tetragonal polymorph of antiferromagnetic CuMnAs by the molecular beam epitaxy technique. We explore the parameter space of growth conditions and their effect on the microstructural and transport properties of the material. We identify its typical structural defects and compare the properties of epitaxial CuMnAs layers grown on GaP, GaAs and Si substrates. Finally, we investigate the correlation between the crystalline quality of CuMnAs and its performance in terms of electrically induced resistance switching.
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