Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA.
Opt Lett. 2011 Sep 15;36(18):3672-4. doi: 10.1364/OL.36.003672.
We incorporate newly developed solid-state detector technology into time-resolved laser Raman spectroscopy, demonstrating the ability to distinguish spectra from Raman and fluorescence processes. As a proof of concept, we show fluorescence rejection on highly fluorescent mineral samples willemite and spodumene using a 128×128 single-photon avalanche diode (SPAD) array with a measured photon detection efficiency of 5%. The sensitivity achieved in this new instrument architecture is comparable to the sensitivity of a technically more complicated system using a traditional photocathode-based imager. By increasing the SPAD active area and improving coupling efficiency, we expect further improvements in sensitivity by over an order of magnitude. We discuss the relevance of these results to in situ planetary instruments, where size, weight, power, and radiation hardness are of prime concern. The potential large-scale manufacturability of silicon SPAD arrays makes them prime candidates for future portable and in situ Raman instruments spanning numerous applications where fluorescence interference is problematic.
我们将新开发的固态探测器技术融入到时间分辨激光拉曼光谱中，展示了区分拉曼和荧光过程光谱的能力。作为概念验证，我们使用具有 5%测量光子探测效率的 128×128 单光子雪崩二极管 (SPAD) 阵列对高度荧光的矿物样品尖晶石和锂辉石进行了荧光抑制。在这种新的仪器架构中实现的灵敏度可与使用传统基于光电阴极的成像仪的技术更复杂的系统的灵敏度相媲美。通过增加 SPAD 有效面积和提高耦合效率，我们预计灵敏度将提高一个数量级以上。我们讨论了这些结果与原位行星仪器的相关性，在原位行星仪器中，尺寸、重量、功率和辐射硬度是首要考虑的因素。硅 SPAD 阵列的大规模制造潜力使它们成为未来便携式和原位拉曼仪器的首选，这些仪器适用于存在荧光干扰问题的众多应用。
