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arXiv · 2507.16161

Broadband coherent Raman spectroscopy based on single-pulse spectral-domain ghost imaging

Jing Hu·Tianjian Lv·Zhaoyang Wen·Wending Huang·Ming Yan·Heping Zeng
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Abstract

Broadband coherent anti-Stokes Raman scattering (CARS) spectroscopy plays a vital role in chemical sensing and label-free vibrational imaging, yet conventional methods suffer from limited acquisition speeds and complex detection schemes. Here, we demonstrate high-speed broadband CARS enabled by nonlinear spectral ghost imaging combined with time-stretch dispersive Fourier-transform spectroscopy (TS-DFT). We exploit modulation instability to generate a stochastic supercontinuum as the Stokes source and a synchronized narrowband pulse as the pump. Reference Stokes spectra are captured at 60.5 MHz via TS-DFT, while anti-Stokes signals are detected using a single non-spectrally resolving photodetector. Correlating these signals enables broadband CARS spectral reconstruction across the fingerprint (600-1600 cm-1) and C-H stretching (2600-3400 cm-1) regions with 13 cm-1 resolution and microsecond-scale acquisition times. Our method enables robust signal recovery without the need for spectral resolution in the detection path, facilitating measurements in complex biological and chemical environments.

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Jing Hu, Tianjian Lv, Zhaoyang Wen, Wending Huang, Ming Yan, Heping Zeng. 2025-07-22. Broadband coherent Raman spectroscopy based on single-pulse spectral-domain ghost imaging. https://arxiv.org/abs/2507.16161

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