Wang Cih-Su, Liau Chi-Shung, Sun Tzu-Ming, Chen Yu-Chia, Lin Tai-Yuan, Chen Yang-Fang
Department of Physics, National Taiwan University, Taipei 106, Taiwan.
Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan.
Sci Rep. 2015 Mar 11;5:8965. doi: 10.1038/srep08965.
A new approach is proposed to light up band-edge stimulated emission arising from a semiconductor with dipole-forbidden band-gap transition. To illustrate our working principle, here we demonstrate the feasibility on the composite of SnO2 nanowires (NWs) and chicken albumen. SnO2 NWs, which merely emit visible defect emission, are observed to generate a strong ultraviolet fluorescence centered at 387 nm assisted by chicken albumen at room temperature. In addition, a stunning laser action is further discovered in the albumen/SnO2 NWs composite system. The underlying mechanism is interpreted in terms of the fluorescence resonance energy transfer (FRET) from the chicken albumen protein to SnO2 NWs. More importantly, the giant oscillator strength of shallow defect states, which is served orders of magnitude larger than that of the free exciton, plays a decisive role. Our approach therefore shows that bio-materials exhibit a great potential in applications for novel light emitters, which may open up a new avenue for the development of bio-inspired optoelectronic devices.
提出了一种新方法来激发具有偶极禁戒带隙跃迁的半导体产生的带边受激发射。为了说明我们的工作原理，在此我们展示了在二氧化锡纳米线（NWs）与鸡蛋白的复合材料上的可行性。仅发射可见缺陷发射光的二氧化锡纳米线，在室温下借助鸡蛋白被观察到产生了以387 nm为中心的强烈紫外荧光。此外，在蛋白/二氧化锡纳米线复合系统中还进一步发现了惊人的激光作用。其潜在机制是根据从鸡蛋白蛋白质到二氧化锡纳米线的荧光共振能量转移（FRET）来解释的。更重要的是，浅缺陷态的巨大振子强度，其比自由激子的振子强度大几个数量级，起到了决定性作用。因此，我们的方法表明生物材料在新型发光体应用中具有巨大潜力，这可能为受生物启发的光电器件的发展开辟一条新途径。
