Fluorescence enhancement in colloidal semiconductor nanocrystals by metallic nanopatterns
Fluorescence enhancement in colloidal semiconductor nanocrystals by metallic nanopatterns
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DOI：
10.1016/j.snb.2006.11.037
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发表时间：
2007-09-20
影响因子：
8.4
通讯作者：
Rinaldi, R.
中科院分区：
文献类型：
--
作者：
Pompa, P. P.;Martiradonna, L.;Rinaldi, R.
在这项工作中，我们证明了通过金属纳米图案显着增加胶体半导体纳米晶体（NC）光致发光的可能性。通过电子束光刻 (EBL) 在平面基底上制造高度有序的三角形金纳米图案（典型尺寸 200 nm）。随后通过旋涂将分散在聚合物基质 (PMMA) 中的胶体半导体纳米晶体（核/壳 CdSe/ZnS 量子点或 CdSe 纳米棒）沉积在基板上。通过共焦显微镜分析探测到，金属纳米结构的表面等离子体（SP）共振带与纳米晶体的激发/发射带之间的耦合导致量子发射器的荧光强烈增强。重要的是，由于 EBL 的纳米分辨率，所提出的方法可以精确控制单个金属纳米结构的形状和尺寸（从而控制 SP 共振）。此外，分散在混合物中的NC的浓度以及活性层的厚度可以进行微调。这些结果可能会为广泛的应用开辟有趣的前景，例如光子器件、LED、传感器技术、微阵列、单/少分子实验以及生物化学/生物物理研究。 (C) 2006 Elsevier B.V. 保留所有权利。
In this work we demonstrate the possibility of obtaining a significant increase of the photoluminescence of colloidal semiconductor nanocrystals (NCs) by means of metallic nanopatterns. Highly ordered triangular-shaped gold nanopatterns (typical dimensions 200 nm) were fabricated on planar substrates by electron beam lithography (EBL). Colloidal semiconductor nanocrystals (core/shell CdSe/ZnS quantum dots or CdSe nanorods) dispersed in a polymer matrix (PMMA) were subsequently deposited on the substrates by spin-coating. The coupling between the surface plasmons (SPs) resonance band of the metallic nanostructures and the excitation/emission bands of the nanocrystals resulted in a strong enhancement of the fluorescence from the quantum emitters, as probed by confocal microscopy analyses. Importantly, the proposed approach allows a precise control of the shape and dimensions of the single metallic nanostructure (and consequently of the SPs resonances), thanks to the nanometer resolution of the EBL. Moreover, the concentration of the NCs dispersed in the blend, as well as the thickness of the active layer, can be finely tuned. These results may open interesting perspectives for a wide range of applications, such as photonic devices, LEDs, sensor technology, microarrays, single/few molecules experiments, and biochemical/biophysical investigations. (C) 2006 Elsevier B.V. All rights reserved.