Room-temperature ferromagnetism of 2H-SiC-α-Al2O3 solid solution nanowires and the physical origin

Abstract

In this work we report the first synthesis of 2H-SiC-α-Al₂O₃ solid solution (SS) nanowires with 2H-SiC as the host phase. The one dimensional (1D) fake binary-system exhibits interesting room-temperature ferromagnetism and spin-glass-like (SGL) behavior. This novel diluted magnetic semiconductor (DMS) was designed on the basis of SiC which is the most promising fundamental semiconductor used in next-generation electronics as the substitute for Si. A systematic investigation of the magnetic properties reveals the origin of the material's room-temperature ferromagnetism and spin-glass behavior. Spin-polarized density functional theory (DFT) calculations reveal that the net moment originates from a strong coupling between atoms around local Si vacancies produced by the SS defect reaction. Unlike random defects derived magnetic behavior, the SS resulted magnetism is significant to be utilized in functional devices since it belongs to a stable crystal structure that is possible to be prepared rationally in a controlled manner.