Defect types and room temperature ferromagnetism in N-doped rutile TiO_2 single crystals  

作　　者：秦秀波 李东翔 李瑞琴 张鹏 李玉晓 王宝义 

机构地区：[1]Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences [2]Division for Nuclear Technology and Application, Institute of High Energy Physics, Chinese Academy of Sciences [3]School of Mathematics and Physics, Anshun University [4]School of Physical Engineering, Zhengzhou University

出　　处：《Chinese Physics B》2014年第6期519-523,共5页中国物理B（英文版）

基　　金：supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.61006066)

摘　　要：The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilation analysis （PAS）. Upon N doping, a twofold enhancement of the saturation magnetization is observed. Apparently, this enhancement is not related to an increase in oxygen vacancy, rather to unpaired 3d electrons in Ti3＋, arising from titanium vacancies and the replacement of O with N atoms in the futile structure. The production of titanium vacancies can enhance the room temperature ferromagnetism （RTFM）, and substitution of O with N is the onset of ferromagnetism by inducing relatively strong ferromagnetic ordering.The magnetic properties and defect types of virgin and N-doped TiO2 single crystals are probed by superconducting quantum interference device （SQUID）, X-ray photoelectron spectroscopy （XPS）, and positron annihilation analysis （PAS）. Upon N doping, a twofold enhancement of the saturation magnetization is observed. Apparently, this enhancement is not related to an increase in oxygen vacancy, rather to unpaired 3d electrons in Ti3＋, arising from titanium vacancies and the replacement of O with N atoms in the futile structure. The production of titanium vacancies can enhance the room temperature ferromagnetism （RTFM）, and substitution of O with N is the onset of ferromagnetism by inducing relatively strong ferromagnetic ordering.

关 键 词：N doping titanium vacancies replacement of 0 with N atoms FERROMAGNETISM 

分 类 号：O482.54[一般工业技术—材料科学与工程]