title: Dual-donor (Zn(i) and V(O)) mediated ferromagnetism in copper-doped ZnO micron-scale polycrystalline films: a thermally driven defect modulation process.
abstract: The paper reports robust ferromagnetic Cu-doped ZnO micron-scale polycrystalline films via spin-coating using high-quality doped nanocrystals. A reliable magnetic response is observed in the 900 °C vacuum annealed film without any ferromagnetic contribution from other sources. Post-annealing treatment in terms of atmosphere and temperature can control the proportion of oxygen vacancies (V(O)) and zinc interstitials (Zn(i)) defects and further help to precisely regulate defect-related ferromagnetic behavior. Complex charge transfer processes derived from dual-donor (Zn(i) and V(O)) to Cu acceptor are revealed by photoluminescence (PL) and electron paramagnetic resonance (EPR) spectra. Based on the above, specific charge transfer (CT)-type Stoner splitting and indirect double-exchange mechanisms are proposed to understand the ferromagnetic origin. The improvable FM performance and annealing-specific modulation further indicate that a thermal driven process can delicately tailor the magnetic property of the transition metal ion-doped ZnO system.
authors.affiliation: State Key Laboratory of Silicon Materials, Dept. of Materials, Zhejiang University, Hangzhou, 310027, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Hu
authors.forename: Jun
authors.initials: J
authors.lastname: Huang
authors.forename: Haiping
authors.initials: H
authors.lastname: He
authors.forename: Liping
authors.initials: L
authors.lastname: Zhu
authors.forename: Shijiang
authors.initials: S
authors.lastname: Liu
authors.forename: Yizheng
authors.initials: Y
authors.lastname: Jin
authors.forename: Luwei
authors.initials: L
authors.lastname: Sun
authors.forename: Zhizhen
authors.initials: Z
authors.lastname: Ye
mesh_terms: D003300:Copper / Q000737:chemistry*; D003460:Crystallization; D004578:Electron Spin Resonance Spectroscopy; D008280:Magnetics; D049329:Nanostructures / Q000737:chemistry; D010084:Oxidation-Reduction; D013696:Temperature; D014639:Vanadium / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D014639:Vanadium; D003300:Copper; D015034:Zinc Oxide