Wang Xiaomu, Tian He, Mohammad Mohammad Ali, Li Cheng, Wu Can, Yang Yi, Ren Tian-Ling
1] Institute of Microelectronics, Tsinghua University, Beijing 100084, China. [2] Tsinghua National Laboratory for Information Science and Technology (TNList), Tsinghua University, Beijing 100084, China.
Nat Commun. 2015 Jul 16;6:7767. doi: 10.1038/ncomms8767.
The continuous tuning of the emission spectrum of a single light-emitting diode (LED) by an external electrical bias is of great technological significance as a crucial property in high-quality displays, yet this capability has not been demonstrated in existing LEDs. Graphene, a tunable optical platform, is a promising medium to achieve this goal. Here we demonstrate a bright spectrally tunable electroluminescence from blue (∼450 nm) to red (∼750 nm) at the graphene oxide/reduced-graphene oxide interface. We explain the electroluminescence results from the recombination of Poole-Frenkel emission ionized electrons at the localized energy levels arising from semi-reduced graphene oxide, and holes from the top of the π band. Tuning of the emission wavelength is achieved by gate modulation of the participating localized energy levels. Our demonstration of current-driven tunable LEDs not only represents a method for emission wavelength tuning but also may find applications in high-quality displays.
通过外部电偏压对单个发光二极管（LED）的发射光谱进行连续调谐，作为高质量显示器的一项关键特性具有重大技术意义，但现有LED尚未展现出这种能力。石墨烯作为一种可调节的光学平台，是实现这一目标的理想介质。在此，我们展示了在氧化石墨烯/还原氧化石墨烯界面处从蓝色（约450纳米）到红色（约750纳米）的明亮的光谱可调谐电致发光。我们解释了电致发光是由半还原氧化石墨烯产生的局域能级上的普尔-弗伦克尔发射电离电子与π带顶部的空穴复合所致。发射波长的调谐通过对参与的局域能级进行栅极调制来实现。我们对电流驱动可调谐LED的展示不仅代表了一种发射波长调谐方法，还可能在高质量显示器中找到应用。
Zotero 插件
