Narrowing of band gap and low-temperature spin glass behavior of FeNi co-doped ZnO nanowiresJaved Iqbal1, Xiaofang Liu1, Abdul Majid2, Dapeng Yu3 and Ronghai Yu1
1 Laboratory of Advanced Materials, Department of Material Science and Engineering, Tsinghua University Beijing 100084, China
2 State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductor, Chinese Academy of Science Beijing 100083, China
3 State Key Laboratory for Mesoscopic Physics, and Electron Microscopy Laboratory, School of Physics, Peking University - Beijing 100871, China
received 26 March 2009; accepted in final form 17 August 2009; published September 2009
published online 17 September 2009
This letter reports on the Raman, optical and magnetic properties of FeNi co-doped ZnO nanowires prepared via a soft chemical solution method. The microstructural investigations show that the NiFe co-dopants are substituted into wurtzite ZnO nanostructure without forming any secondary phase. The co-doped nanowires show a remarkable reduction of 34 nm (267.9 meV) in the optical band gap, while suppression in the deep-level defect transition in visible luminescence. Furthermore, these nanowires exhibit ferromagnetism and an interesting low-temperature spin glass behavior, which may arise due to the presence of disorder and strong interactions of frustrated spin moments of Ni and Fe co-dopants on the ZnO lattice sites.
74.25.Gz - Optical properties.
74.25.Ha - Magnetic properties.
© EPLA 2009