Room-temperature ferromagnetism induced by Cu vacancies in Cu x(Cu2O)1− x granular films
Xie Xin-Jiana), Li Hao-Bob), Wang Wei-Chaob), Lu Fengb), Yu Hong-Yunc), Wang Wei-Hua†b), Cheng Ya-Hui‡b), Zheng Rong-Kund), Liu Huib)
       
TEM images of the granular films sputtered in the different oxygen flow rates at (a) 2.0 sccm, (b) 3.0 sccm, (c) 3.4 sccm, and (d) 4.0 sccm, respectively.