Fe-doped ZnO film has been grown by laser molecular beam epitaxy（L-MBE） and structurally characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,all of which reveal the high quality of the ...Fe-doped ZnO film has been grown by laser molecular beam epitaxy（L-MBE） and structurally characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,all of which reveal the high quality of the film.No secondary phase was detected.Resonant photoemission spectroscopy（RPES） with photon energies around the Fe 2p-3d absorption edge is performed to detect the electronic structure in the valence band.A strong resonant effect at a photon energy of 710 eV is observed.Fe3＋ is the only valence state of Fe ions in the film and the Fe 3d electronic states are concentrated at binding energies of about 3.8 eV and 7 eV～8 eV.There are no electronic states related to Fe near the Fermi level.Magnetic measurements reveal a typical superparamagnetic property at room temperature.The absence of electronic states related to Fe near the Fermi level and the high quality of the film,with few defects,provide little support to ferromagnetism.展开更多
Cu- and Ni-codoped FeZnO particles with the wurzite structure were successfully synthesized at low temperature by a co-precipitation method. The samples were characterized using a vibrating sample magnetometer, X-ray ...Cu- and Ni-codoped FeZnO particles with the wurzite structure were successfully synthesized at low temperature by a co-precipitation method. The samples were characterized using a vibrating sample magnetometer, X-ray diffraction, energy dispersive X-ray spectroscopy, UV-Vis spectrophotometry and electron spin resonance. The results demonstrated that room temperature ferromagnetic order was observed in both samples and the magnetization was higher than that of Fe-doped ZnO. The correlation between the structural and magnetic properties is discussed.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10775126 and 10975138)
文摘Fe-doped ZnO film has been grown by laser molecular beam epitaxy（L-MBE） and structurally characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,all of which reveal the high quality of the film.No secondary phase was detected.Resonant photoemission spectroscopy（RPES） with photon energies around the Fe 2p-3d absorption edge is performed to detect the electronic structure in the valence band.A strong resonant effect at a photon energy of 710 eV is observed.Fe3＋ is the only valence state of Fe ions in the film and the Fe 3d electronic states are concentrated at binding energies of about 3.8 eV and 7 eV～8 eV.There are no electronic states related to Fe near the Fermi level.Magnetic measurements reveal a typical superparamagnetic property at room temperature.The absence of electronic states related to Fe near the Fermi level and the high quality of the film,with few defects,provide little support to ferromagnetism.
文摘Cu- and Ni-codoped FeZnO particles with the wurzite structure were successfully synthesized at low temperature by a co-precipitation method. The samples were characterized using a vibrating sample magnetometer, X-ray diffraction, energy dispersive X-ray spectroscopy, UV-Vis spectrophotometry and electron spin resonance. The results demonstrated that room temperature ferromagnetic order was observed in both samples and the magnetization was higher than that of Fe-doped ZnO. The correlation between the structural and magnetic properties is discussed.
