Optical and magnetic properties of nitrogen ion implanted MgO single crystal

Abstract

The microstructure, optical property and magnetism of nitrogen ion implanted single MgO crystals are studied. A parallel investigation is also performed in an iron ion implanted single MgO sample as a reference. Large structural, optical and magnetic differences are obtained between the nitrogen and iron implanted samples. Room temperature ferromagnetism with a fairly large coercivity field of 300 Oe (1 Oe=79.5775 A/m), a remanence of 38% and a slightly changed optical absorption is obtained in the sample implanted using nitrogen with a dose of 1×10 18 ions/cm 2 . Transition metal contamination and defects induced magnetism can be excluded when compared with those of the iron ion implanted sample, and the nitrogen doping is considered to be the main origin of ferromagnetism.

Catalytic growth of N-doped MgO on Mo(001)

“…A Curie temperature T C 550 K has been extrapolated and indications that N is incorporated substitutionally on the O site have been deduced from core level spectroscopy. Moreover, independent studies of N implantation (80 keV) into MgO has led to a hysteresis with a coercive field of 30 mT at 300 K. 2 This raises hope that reliable d 0 ferromagnetism avoiding d metals can be realized in MgO:N at T = 300 K. Such magnetism without d orbitals has previously been found in thin films of undoped oxides 3 including MgO (Ref. 4) or defective carbon systems, 5 however, with limited control since relying on defects.…”

“…15 It requires, for example, atomic beams of N and O produced by a high-frequency ion plasma source 1 or N + implantation. 2 Here, we demonstrate a simplified pathway using the catalytic abilities of a Mo(001) substrate. Thus, we establish a model system of MgO:N for surface science.…”

Half-metallic ferromagnetism in C-doped zinc-blende ZnO: A first-principles study

“…[7][8][9] To avoid these questions, some semiconductors doped with nonmagnetic elements such as Cu, Ca, C, and N were investigated, and the results verified that nonmagnetic elements can induce ferromagnetism. [10][11][12][13][14] Pan et al [15] predicted ferromagnetism in C-doped wurtzite ZnO by first-principles calculations and then confirmed their prediction by fabricating C-doped ZnO films with Curie temperature higher than 400 K via pulsed laser deposition. Subsequently, Zhou et al [16] produced C-implanted ZnO films with RT ferromagnetism by ion implantation.…”

Study of the magnetism of C-doped MgO based on first-principles calculations and the Ising model

“…31 Regardless of Cdoped or N-doped MgO, it is the result of a delicate interplay between Hund's coupling, hybridization and Jahn-Teller distortion, and the dopant creates a localized magnetic moment and leaves the whole system in a half-metallic ferromagnetic state. [31][32][33][34][35][36][37][38] Even in undoped MgO thin films, the ferromagnetism was also found in experiments at room temperature, and the magnetization in the MgO matrix is believed to be defect induced. 39 The Ising model is widely used in exploring the underlying physics behind phase transitions and the magnetism of materials.…”