Schwarz Benedikt, Reininger Peter, Ristanić Daniela, Detz Hermann, Andrews Aaron Maxwell, Schrenk Werner, Strasser Gottfried
Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, Vienna 1040, Austria.
Nat Commun. 2014 Jun 6;5:4085. doi: 10.1038/ncomms5085.
The increasing demand of rapid sensing and diagnosis in remote areas requires the development of compact and cost-effective mid-infrared sensing devices. So far, all miniaturization concepts have been demonstrated with discrete optical components. Here we present a monolithically integrated sensor based on mid-infrared absorption spectroscopy. A bi-functional quantum cascade laser/detector is used, where, by changing the applied bias, the device switches between laser and detector operation. The interaction with chemicals in a liquid is resolved via a dielectric-loaded surface plasmon polariton waveguide. The thin dielectric layer enhances the confinement and enables efficient end-fire coupling from and to the laser and detector. The unamplified detector signal shows a slope of 1.8-7 μV per p.p.m., which demonstrates the capability to reach p.p.m. accuracy over a wide range of concentrations (0-60%). Without any hybrid integration or subwavelength patterning, our approach allows a straightforward and cost-saving fabrication.
偏远地区对快速传感和诊断的需求不断增加，这就需要开发紧凑且经济高效的中红外传感设备。到目前为止，所有小型化概念都是通过分立光学元件来实现的。在此，我们展示了一种基于中红外吸收光谱的单片集成传感器。使用了一种双功能量子级联激光器/探测器，通过改变施加的偏置，该器件可在激光和探测器操作之间切换。与液体中化学物质的相互作用通过介质加载表面等离子体激元波导来解析。薄介质层增强了限制作用，并实现了与激光器和探测器之间高效的端射耦合。未放大的探测器信号显示出每百万分之一为1.8 - 7 μV的斜率，这表明在很宽的浓度范围（0 - 60%）内能够达到百万分之一的精度。无需任何混合集成或亚波长图案化，我们的方法允许进行直接且节省成本的制造。
