Høgstedt Lasse, Dam Jeppe Seidelin, Sahlberg Anna-Lena, Li Zhongshan, Aldén Marcus, Pedersen Christian, Tidemand-Lichtenberg Peter
Opt Lett. 2014 Sep 15;39(18):5321-4. doi: 10.1364/OL.39.005321.
We compare a nonlinear upconversion detector with a conventional cryogenic InSb detector for the detection of coherent infrared light showing near-shot-noise-limited performance in the upconversion system. The InSb detector is limited by dark noise, which results in a 500 times lower signal-to-noise ratio. The two detectors are compared for the detection of a coherent degenerate four-wave mixing (DFWM) signal in the mid-infrared, and applied to measure trace-level acetylene in a gas flow at atmospheric pressure, probing its fundamental rovibrational transitions. In addition to lower noise, the upconversion system provides image information of the signal, thus adding new functionality compared to standard point detection methods. We further show that the upconversion detector system can be implemented as a simple replacement of the cryogenic detector.
我们将一种非线性上转换探测器与传统的低温铟锑探测器进行比较，用于检测相干红外光，该上转换系统表现出接近散粒噪声极限的性能。铟锑探测器受暗噪声限制，导致信噪比降低500倍。比较了这两种探测器对中红外相干简并四波混频（DFWM）信号的探测能力，并将其应用于测量大气压下气流中的痕量乙炔，探测其基本振转跃迁。除了更低的噪声外，上转换系统还提供信号的图像信息，因此与标准点探测方法相比增加了新功能。我们进一步表明，上转换探测器系统可以作为低温探测器的简单替代品来实现。
