First-Principles Prediction of Ferromagnetism in Single-walled (6,0) SiC:Au Nanotubes

Single-walled (6, 0) gold-doped SiC nanotubes (SWSiC: AuNT) were systematically studied using first-principles density functional theory (DFT) calculations within the LSDA [Formula: see text] Hubbard U framework. Our results reveal that Au doping significantly modifies the electronic structure of the pristine SiC nanotube, inducing half-metallic behavior characterized by a semiconducting majority spin channel with a band gap of approximately 0.8[Formula: see text]eV and a metallic minority spin channel. Partial density of states analysis indicates that states near the Fermi level primarily originate from hybridization between carbon 2p orbitals and gold 4d orbitals. Mulliken population and spin density analyses show that the net magnetic moment ([Formula: see text] predominantly arises from three carbon atoms chemically bonded to the Au dopant. Total energy calculations predict that the antiferromagnetic configuration is energetically favored, suggesting stable magnetic ordering. Additionally, formation energy and structural relaxation studies confirm the thermodynamic and mechanical stability of the Au-doped SiC nanotube system, highlighting its potential for spintronic and nanoscale magnetic device applications.