Half-Metallic Ferromagnetism in TM-Doped GaN Nanosheet — A Potential Candidate for Spintronics Device Application.

Density functional theory (DFT) analyses were carried out to study electronic structures and magnetic properties of Mn- and Cu-doped GaNNS. To investigate the influence of transition metal atoms (TM) on magnetic properties, we substituted Ga atoms with Mn and Cu atoms in different concentrations. Investigation shows that TM leads to electronic structural reconstruction which changes their properties in this way, and plays a significant role in spin polarization. Although the pure nanosheet is a nonmagnetic semiconductor, the doped atoms induce magnetism in the structure. The band gap changes monotonically depending on the concentration of TM atoms. The observed good half-metal ferromagnetism GaNNS:Mn, allows them to be a potential candidate for use in spintronics. The local magnetic moment calculated from Mulliken analyses for the Mn atom is approximately 4.05 μ B. By choosing the appropriate concentration of impurity atoms one can obtain a magnetic semiconductor and is half-metal. Thus, Mn-atoms may induce half-metallic ferromagnetism in GaN nanosheet, which makes it a potential candidate for spintronics device applications. Also observed, was weak ferromagnetism in Cu-doped GaNNS is not suitable for use in spintronics. [ABSTRACT FROM AUTHOR]