Spatial heterodyne spectrometers are members of the static Fourier transform class of spectrometers, well-regarded for their ability to acquire high-resolution, high wavelength precision emission spectra in compact, light footprint packages. In a spatial heterodyne spectrometer experiment, a Fizeau fringe is generated for every spectral feature in a given spectrum, and spatial heterodyne spectrometer records the superposition of all Fizeau fringes in the spectrum on a detector. Hence, the sensitivity of spatial heterodyne spectrometers is constrained by uncorrelated, multiplicative photon noise that limits the detection of spectral features to those that are more luminous than the square root of the total incident flux onto the detector. In essence, powerful spectral features create a rising floor of noise that wash out less luminous features. In the present work, we introduce a novel spectrometer coupling, that being an Amici prism spectrometer in series with spatial heterodyne spectrometer, that correlates photon shot noise along one axis of a detector that in turn suppresses multiplicative photon noise within each row of the interferogram image. We demonstrate that this spectrometer pairing facilitates the measurement of weak Raman spectral features that, in a traditional spatial heterodyne spectrometer measurement, would be washed out by multiplicative photon noise.

中文翻译：

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EXPRESS：使用交叉色散空间外差光谱法抑制光子噪声限制干涉测量中的多路复用缺点

空间外差光谱仪是静态傅立叶变换类光谱仪的成员，因其在紧凑、轻便的封装中获取高分辨率、高波长精确发射光谱的能力而备受推崇。在空间外差光谱仪实验中，对给定光谱中的每个光谱特征都会产生一个斐索条纹，空间外差光谱仪将光谱中所有斐索条纹的叠加记录在探测器上。因此，空间外差光谱仪的灵敏度受到不相关的乘性光子噪声的限制，这将光谱特征的检测限制为比检测器上总入射通量的平方根更明亮的特征。从本质上讲，强大的光谱特征会产生一个上升的噪声底，从而冲刷掉亮度较低的特征。在目前的工作中，我们引入了一种新型的光谱仪耦合，即与空间外差光谱仪串联的 Amici 棱镜光谱仪，它将沿探测器一个轴的光子散粒噪声关联起来，进而抑制干涉图图像每一行内的乘法光子噪声. 我们证明，这种光谱仪配对有助于测量弱拉曼光谱特征，在传统的空间外差光谱仪测量中，这些特征会被倍增光子噪声冲刷掉。