Nitrogen embedded ZnO:N films prepared by pulsed laser deposition exhibit significant ferromagnetism. The nitrogen ions contained in ZnO confirmed by Secondary Ion Microscopic Spectrum and Raman experiments and the embedded nitrogen ions can be regarded as defects. According to the experiment results, a mechanism is proposed based on one of the electrons in the completely filled dorbits of Zn that compensates the dangling bonds of nitrogen ions and leads to a net spin of one half in the Zn orbits. These one half spins strongly correlate with localized electrons that are captured by defects to form ferromagnetism. Eventually, the magnetism of nitrogen embedded ZnO:N films could be described by a bound magnetic polaron model.

Within a special kind of slave-boson mean-Geld approximation, which allows for the symmetrybroken states appropriate for a bipartite lattice, it is found that there is a phase transition to the antiferromagnetic insulator for the symmetric periodic Anderson model, and the critical value of the hybridization matrix element is consistent with the quantum Monte Carlo result of Jarrell, Akhlaghpur, and Pruschke [Phys. Rev. Lett. 70, 1670]. Our results suggest that the

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The phonon spectrum has in recent years attracted much interest in investigating electrical transfer in nanowires. In this study, molecular dynamics is employed to calculate the phonon property of thinness for 7-1 gold nanowire at room temperature. This study finds that the phonon density distribution of 7-1 nanowire is different from both that of bulk face-centred cubic (fcc) structure and that of nanoparticles. We also observed that the high frequency of the phonon spectrum in the bulk fcc structure has a higher intensity than the low frequency of the phonon spectrum. This phenomenon, however, does not appear in the 7-1 nanowire. The strain effect of 7-1 nanowire on the phonon property has also been studied; moreover, the phonon spectra of core–core and shell–shell structures of nanowire exhibit two different modes. The relationship between the phonon profile of these core and shell structures is analysed in this study.

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We studied the exchange interactions mediated by polarized itinerant carriers in diluted magnetic semiconductor (DMS) junction. In contrast to the ordinary RKKY oscillations, the induced moment possesses an interesting spiral motion, accompanied with angular oscillations. The spiral motion remains robust in the entire T < Tc regime while the oscillatory motion gets enhanced as T → Tc. To explore the novel phenomena, we propose a ferromagnet/DMS/ferromagnet junction would bring out interesting spin-dependent transport properties and possible applications in spintronics.