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Adaptive Terahertz Dual Frequency Comb Spectrometer



Flavio Caldas da Cruz, Francisco S. Vieira, David F. Plusquellic, Scott A. Diddams


Terahertz dual frequency comb spectroscopy (THz-DFCS) yields high spectral resolution without compromising bandwidth. Nonetheless, the resolution of THz-DFCS is usually limited by the laser repetition rate, which is typically between 80 MHz and 1 GHz. In this paper, we demonstrate a new method to achieve sub-repetition rate resolution in THz-DFCS by adaptively modifying the effective laser repetition rate using integrated Mach-Zehnder electro-optic modulators (MZ-EOMs). Our results demonstrate that it is possible to improve the 100 MHz resolution of a terahertz frequency comb by at least 20x (down to 5 MHz) across the terahertz spectrum without compromising the average output power, and to a large extent, its bandwidth. Our approach can augment a wide range of existing THz-DFCS systems to provide a significant and easily adaptable resolution improvement.
Optics Express


Terahertz frequency comb, terahertz spectroscopy, dual-frequency comb spectroscopy


Caldas, F. , Vieira, F. , Plusquellic, D. and Diddams, S. (2016), Adaptive Terahertz Dual Frequency Comb Spectrometer, Optics Express (Accessed April 22, 2024)
Created December 26, 2016, Updated February 19, 2017