Zeng Zhi-Cong, Schultz Zachary D
Department of Chemistry and Biochemistry, Ohio State University, Columbus, Ohio 43210, USA.
Rev Sci Instrum. 2018 Aug;89(8):083105. doi: 10.1063/1.5036626.
We report a compact, fast, and low-noise large area photodiode preamplifier designed for photothermal heterodyne imaging (PHI). The preamplifier exhibits a noise level of 7 nV/Hz and a bandwidth from DC to 12 MHz sufficient for PHI experiments. Simulations of the preamplifier bandwidth and noise agree with the observed experimental characterization and performance in our home-built PHI system. The observed noise is close to the inherent limitations of the SR844 lock-in amplifier used. The results indicate that the preamplifier is also useful for any other single frequency pump-probe detection technique, such as stimulated Raman scattering.
我们报道了一种为光热外差成像（PHI）设计的紧凑、快速且低噪声的大面积光电二极管前置放大器。该前置放大器的噪声水平为7 nV/Hz，直流到12 MHz的带宽足以满足PHI实验需求。对该前置放大器带宽和噪声的模拟结果与我们在自制PHI系统中观察到的实验特性及性能相符。观察到的噪声接近所用SR844锁相放大器的固有极限。结果表明，该前置放大器对任何其他单频泵浦 - 探测检测技术（如受激拉曼散射）也同样有用。
