Rahomäki Jussi, Nuutinen Tarmo, Karvonen Lasse, Honkanen Seppo, Vahimaa Pasi
University of Eastern Finland, Department of Physics and Mathematics, P.O. Box 111, 80101 Joensuu, Finland.
Opt Express. 2013 Apr 8;21(7):9060-8. doi: 10.1364/OE.21.009060.
Herein we characterize and experimentally demonstrate a new type of a horizontal slot waveguide structure for remarkably enhanced Raman scattering detection in nanometer-scale void channels. As the measurement sensitivity is one of the key limiting factors in nanofluidic detection, it is essential to search advanced solutions for such detection. Combining an all dielectric resonance waveguide grating and a surface enhanced Raman scattering (SERS) substrate in a close proximity it is possible to create high electromagnetic field energy hot zones within an adjustable slot region. This results in a strong enhancement in Raman scattering. We show the theoretical principles and demonstrate, with rhodamine 6G molecules, an approximately 20-fold enhancement compared to a conventional SERS substrate within the corresponding slot arrangement. We foresee potential applications for the proposed approach in the fields of medical, biological and chemical sensing, where the high detection sensitivity is essential due to integration with nanofluidic devices.
在此，我们对一种新型水平狭缝波导结构进行了表征并通过实验证明，该结构可在纳米级空隙通道中显著增强拉曼散射检测。由于测量灵敏度是纳米流体检测中的关键限制因素之一，因此寻找此类检测的先进解决方案至关重要。将全介质共振波导光栅和表面增强拉曼散射（SERS）基底紧密结合，有可能在可调节的狭缝区域内产生高电磁场能量热点。这导致拉曼散射得到强烈增强。我们展示了理论原理，并使用罗丹明6G分子证明，在相应的狭缝排列中，与传统SERS基底相比，增强了约20倍。我们预见到所提出的方法在医学、生物和化学传感领域的潜在应用，在这些领域中，由于与纳米流体装置集成，高检测灵敏度至关重要。
