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arXiv · 1812.03505

Terahertz hyperspectral imaging with dual chip-scale combs

Lukasz A. Sterczewski·Jonas Westberg·Yang Yang·David Burghoff·John Reno·Qing Hu·Gerard Wysocki
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Abstract

Hyperspectral imaging is a technique that allows for the creation of multi-color images. At terahertz wavelengths, it has emerged as a prominent tool for a number of applications, ranging from non-ionizing cancer diagnosis and pharmaceutical characterization to non-destructive artifact testing. Contemporary terahertz imaging systems typically rely on non-linear optical down-conversion of a fiber-based near-infrared femtosecond laser, requiring complex optical systems. Here, we demonstrate hyperspectral imaging with chip-scale frequency combs based on terahertz quantum cascade lasers. The dual combs are free-running and emit coherent terahertz radiation that covers a bandwidth of 220 GHz at 3.4 THz with ~10 μW per line. The combination of the fast acquisition rate of dual-comb spectroscopy with the monolithic design, scalability, and chip-scale size of the combs is highly appealing for future imaging applications in biomedicine and in the pharmaceutical industry.

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Lukasz A. Sterczewski, Jonas Westberg, Yang Yang, David Burghoff, John Reno, Qing Hu, Gerard Wysocki. 2018-12-09. Terahertz hyperspectral imaging with dual chip-scale combs. https://arxiv.org/abs/1812.03505

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