SBIR Phase II: Low Cost On-Chip Photonic Crystal Slot Waveguide Absorption Spectrometer for Highly Sensitive, Continuous,In-Situ,Remote Specific Detection of Multiple VOC in Water

该小型企业创新研究（SBIR）第二阶段项目建议开发一种低成本封装的近红外片上硅吸收光谱仪，用于同时和特定检测水中（地下水，废水和饮用水）的多种挥发性有机化合物。 在第一阶段，通过近红外吸收特征，在具有300微米长的光子晶体槽波导的芯片上成功地检测了水中100 ppm的挥发性有机化合物二甲苯，这代表了设备灵敏度和小型化的最佳结果。 该器件将光子晶体波导中的慢光效应与光子晶体波导中心的低折射率槽中的高度集中的光场强度相结合。 本文提出的光子晶体槽波导提供了一个1000倍的减少，在相互作用的长度相比，传统的波导导致增强的光路中的分析物的光吸收。传输是从多个波导覆盖整个近红外波长范围内测量，并通过测量在存在和不存在的任何挥发性有机化合物的分析物ofinterest的透射差异确定的吸光度。 微型光谱仪将实现大规模并行识别和高通量分析。这项研究的更广泛的影响是能够连续，远程，原位监测和独特的识别地下水，饮用水和废水中的多种挥发性有机化合物（VOC），具有高灵敏度和特异性，目前还没有商业化的设施。 集成的硅平台可确保大批量低成本生产。从商业角度来看，联合国环境规划署估计，到2020年，全球水市场将从目前的2500亿美元扩大到6600亿美元。 所提出的光子晶体缝隙波导器件有望在这一市场中占据重要地位。 所提出的通用技术的一般化设计意味着在具有低拥有成本的芯片实验室平台中，在原位分析物感测、检测和光谱学的多个领域（诸如食物、空气和水质和健康的控制）中可能实现。 通过连续、现场和远程监测，这项研究开发的原型将消除目前工业水监测中存在的滞后时间，有时会延长到几个月，如河流和湖泊的挥发性有机化合物监测，从而能够对虚假泄漏和溢出进行早期预警，而不是事后的损害控制和调解，从而加强环境和国家安全。

This Small Business Innovation Research (SBIR) Phase II project proposes to develop a low cost packaged near-infrared on-chip silicon absorption spectrometer for simultaneous and specific detection of multiple volatile organic compounds in water (ground water, waste water and drinking water). In phase I, the volatile organic compound xylene was successfully detected in water at 100 parts per billion through near-infrared absorption signatures, on chip with 300 micron long photonic crystal slot waveguides which represents the best results in device sensitivity and in miniaturization. The device combines slow light effect in photonic crystal waveguides with highly concentrated optical field intensity in a low index slot at the center of the photonic crystal waveguide. The photonic crystal slot waveguide proposed herein provides a factor of 1000 reduction in interaction length compared to conventional waveguides leading to enhanced optical absorption by analytes in the optical path. Transmission is measured from multiple waveguides covering the entire near-infrared wavelength range, and absorbance determined by measuring transmission differences in the presence and the absence of any volatile organic compound analytes ofinterest. The miniature spectrometer will enable massively parallel identification and high throughput analysis. The broader impacts of this research are the enabling of continuous, remote, in-situ monitoring and unique identification of multiple volatile organic compounds (VOCs) in groundwater, drinking water, and waste water, with high sensitivity and specificity, a facility that is not available commercially at present. The integrated siliconplatform ensures low cost production in high volume. From commercial standpoint, the United Nations Environment Program estimates the global water market to expand to $660 billion from the current $250 billion by 2020. The proposed photonic crystal slot waveguide device can be expected to occupy a significant position in this market. The generalized design of the proposed versatile technology implies possible implementation in multiple areas of in-situ analyte sensing, detection, and spectroscopy such as control of food, air, and water quality and health, in a lab-on-chip platform with low cost of ownership. Through continuous, in-situ and remote monitoring, the prototype developed from this research will eliminate the lag time that currently exists in industrial water monitoring, sometimes extending to few months as in VOC monitoring of rivers and lakes, thereby enabling early warning of spurious leaks and spills instead of after-the-fact damage control and mediation and thus enhance environmental and national security.