Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78712, USA.
Opt Lett. 2011 Mar 15;36(6):984-6. doi: 10.1364/OL.36.000984.
We demonstrate a 300 μm long silicon photonic crystal (PC) slot waveguide device for on-chip near-infrared absorption spectroscopy, based on the Beer-Lambert law for the detection of methane gas. The device combines slow light in a PC waveguide with high electric field intensity in a low-index 90 nm wide slot, which effectively increases the optical absorption path length. A methane concentration of 100 ppm (parts per million) in nitrogen was measured.
我们展示了一种 300μm 长的硅光子晶体（PC）条形波导器件，用于基于比尔-朗伯定律的近红外吸收光谱学，以检测甲烷气体。该器件结合了 PC 波导中的慢光和低折射率 90nm 宽槽中的高电场强度，有效地增加了光吸收路径长度。在氮气中测量到了 100ppm（百万分之一）的甲烷浓度。
