Epitaxial Growth and Magnetic Properties of NiMnAs Films on GaAs Substrates**Supported by the National Key Research and Development Program of China under Grant No 2017YFB0405701, the National Natural Science Foundation of China under Grant Nos U1632264 and 11706374, and the Key Research Project of Frontier Science of Chinese Academy of Science under Grant No QYZDY-SSW-JSC015.

Abstract

Single-phase Ni0.92Mn1.08As films with strained C1b symmetry are grown on GaAs (001) substrates. In addition, a preferred epitaxial configuration of (110)-orientated Ni0.92Mn1.08As on (001)-orientated GaAs is revealed by synchrotron radiation measurement. The magnetic properties of the films are found to be significantly influenced by the growth temperature and the optimized growth temperature is determined to be ∼370°C. According to the results of x-ray absorption spectroscopy, these phenomena can be attributed to the variation of the local electronic structure of the Mn atoms. Our work provides useful information for the further investigations of NiMnAs, which is a theoretically predicted half-metal.