title: Ferromagnetism in sphalerite and wurtzite CdS nanostructures.
abstract: Room-temperature ferromagnetism is observed in undoped sphalerite and wurtzite CdS nanostructures which are synthesized by hydrothermal methods. Scanning electron microscopy and transmission electron microscopy results indicate that the sphalerite CdS samples show a spherical-like shape and the wurtzite CdS ones show a flower-like shape, both of which are aggregated by lots of smaller particles. The impurity of the samples has been ruled out by the results of X-ray diffraction, selected-area electron diffraction, and X-ray photoelectron spectroscopy. Magnetization measurements indicate that all the samples exhibit room-temperature ferromagnetism and the saturation magnetization decreases with the increased crystal sizes, revealing that the observed ferromagnetism is defect-related, which is also confirmed by the post-annealing processes. This finding in CdS should be the focus of future electronic and spintronic devices.
authors.affiliation: Key Laboratory for Magnetism and Magnetic Materials of MOE, Lanzhou University, Lanzhou, 730000, People's Republic of China. xueds@lzu.edu.cn.
authors.forename: Zhaolong
authors.initials: Z
authors.lastname: Yang
authors.forename: Daqiang
authors.initials: D
authors.lastname: Gao
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Zhu
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Shi
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Zhang
authors.forename: Desheng
authors.initials: D
authors.lastname: Xue