First principles study of structural, electronic and magnetic properties of transition metals doped SiC monolayers for applications in spintronics

摘要

First principles investigations were carried out to explore the prospects of using silicon carbide (SiC) monolayers in spintronics. The structural, electronic and magnetic properties of Ti, V, Cr, Mn and Fe doped SiC monolayers were studied in detail in framework of density functional theory (DFT). These dopants changed the band structure of SiC by introducing gap states and thus altered the electronic and magnetic character of the host. The results indicated that Ti did not produce any magnetic state whereas Mn and Cr exhibited ferromagnetism (FM), and V as well as Fe displayed anti-ferromagnetism (AFM) as stable configurations in the matrix. The calculated values of magnetic moments are 0 μ_B, 1.24 μ_B, 2.37 μ_B. 3.01 μ_B, and 2.21 μ_B for dopants Ti, V, Cr, Mn and Fe respectively in the host. The dopants reveal 3d-2p hybridization with exchange interactions taking place through charge hopping. The analysis indicated that magnetic exchange takes place in Mn:SiC and Fe:SiC via super-exchange whereas in Cr:SiC via double exchange interactions. The Mn doped SiC monolayer appeared to offer highest Curie temperatures with half metallic nature and highest magnetic moment which points to its suitability as potential diluted magnetic semiconductor for different spintronic applications.