On the Cover: Individual Ga-doped ZnO microwires covered by Au nanorods: wavelength-tunable incandescent-type light sources
Electrically driven strong light-emitting from individual ZnO:Ga MWs based devices were realized with tunable colors, and the emission region is localized towards the center of MWs, which can be treated as a typical incandescent filament lamp. They attached an individual ZnO:Ga MW to metal electrodes, directly on the substrate, and passed a current through the filaments to cause them lighting. The bright lighting is so intense that it can be clearly observed by naked eyes in normal indoor lighting conditions. Corresponding light-emitting can be derived from Ga-dopant induced impurity band and Joule heating effect, but cannot be compatible with thermoluminescence. By adjusting the length of MWs, lighting emitters can be tuned from elongated lighting sources to spot lighting sources. Meanwhile, owing to the absence of rectification characteristics, relevant electrical measurement results show that the alternating current-driven light-emitting functions excellently on the ZnO:Ga MWs. Specially, by incorporating Au nanorods with controlled sizes, the dominating emission peak wavelengths of single ZnO:Ga MW based incandescent-type filament light source can be redshifted into near-infrared spectral band. Relevant research results are published in Photonics Research, Vol.8, Issue 1, 2020(Zhipeng Sun, Mingming Jiang, Wangqi Mao, Caixia Kan, Chongxin Shan, Dezhen Shen. Nonequilibrium hot-electron-induced wavelength-tunable incandescent-type light sources[J]. Photonics Research, 2020, 8(1): 01000091).