摘要
ZnO的激子束缚能高达60meV,具有优良的光学性质。因此,Mn掺杂的ZnO材料研究在磁性半导体领域广泛开展起来。文章采用溶胶-凝胶法制备了Mn掺杂的ZnO纳米晶,讨论了在不同退火温度下纳米晶的结构和磁性。XRD结果显示,所有样品均为六角纤锌矿结构。退火后,Mn掺杂ZnO纳米晶的晶格常数均略大于纯净ZnO的晶格常数,表明Mn2+已经替代Zn2+进入ZnO晶格。500℃退火的样品在4～300K温度范围内表现为顺磁性。将退火温度提高到900℃后,有少量尖晶石结构的ZnMn2O4存在。室温磁滞回线表明样品具有室温铁磁性,磁性来源于ZnMn2O4。
ZnO is a wide band-gap semiconductor with the high exciton binding energy of 60 meV. The ZnO-based DMS therefore attracts extensive interesting. Mn-doped ZnO nanocrystals were fabricated by sol-gel method. Structure and magnetism of these nanocrystals annealed at different temperature were investigated. XRD spectra show all the films are hexagonal wurtzite structures and the lattice constants were larger than that of pure ZnO after annealing, which indicates that Mn has entered the ZnO lattice and substituted the Zn site. The sample annealed at 500 ℃ showed paramagnetic at 4-300 K. A little ZnMn2O4 were found after annealing at 900 ℃. Room-temperature hysteretic loop proved that ferromagnetic ordering arises from ZnMn2O4 in all probability.
出处
《液晶与显示》
CAS
CSCD
北大核心
2007年第1期11-14,共4页
Chinese Journal of Liquid Crystals and Displays
基金
国家自然科学基金资助项目(No.10647105
No.50402016
No.60501025
No.60506014)
国家自然科学基金重点项目(No.60336020
No.50532050)
中国科学院创新项目(2004年第7号)
