Ferromagnetism in Carbon-Doped Zinc Oxide Systems

Abstract

We report spin polarized density functional calculations of ferromagnetic properties of a series of ZnO clusters and solid containing one or two substitutional carbon impurities. We analyze the eigen value spectra, spin densities and molecular orbitals, and induced magnetic moments for ZnC, Zn2C, Zn2OC, carbon substituted clusters ZnnOn (n=3-10, 12) and ZnO solid. The results show that the doping induces magnetic moment of the ∼2 µB in all the cases. All the systems with two carbon impurities show ferromagnetic interaction except when the carbon atoms share the same Zn atom as the nearest neighbor. This ferromagnetic interaction is predominantly mediated via π bonds in ring structures and through π and σ bonds in three dimensional structure. The calculations also show that the interaction is significantly enhanced in solid, bringing out the role of dimensionality of Zn-O network connecting two carbon atoms.

Carbon doped ZnO: Synthesis, characterization and interpretation

“…There are recent claims for RT ferromagnetism in carbon doped ZnO [22][23][24][25][26][27]. In line with the understanding of magnetism, as stated before, the question about the origin of magnetic moment does arise since there are no TM elements doped in the samples.…”

First-principles study on ferromagnetism in C-doped AlN

“…Besides the discovery of ferromagnetism in nonmagnetic cation doped semiconductors, the experimental researches demonstrated that high temperature ferromagnetism also can be obtained in nonmagnetic anion C-and N-doped ZnO and TiO 2 and C-doped GaN [10][11][12][13][14][15][16][17][18][19]. Furthermore, first-principles calculations reported that anion C or N substitutions in several oxides, sulfides and nitrides can induce ferromagnetism and the ferromagnetism is intrinsic [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34].…”

Magnetoelectrical properties of W doped ZnO thin films

“…One of the widely investigated semiconductors is ZnO, at which magnetic formation depending on point defects has been revealed [1]. On the other hand, the findings point the ferromagnetism with doping of nonmagnetic elements as well, such as Al [5], Zn [5], Pt [5] and C [6] due to the p-p interactions in between 2p energy levels of cations (O, N, As etc.) and impurity band levels [5,6].…”