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arXiv · 1810.09118

Terahertz generation by beamlet superposition

Koustuban Ravi·Benjamin Ofori-Okai·Keith A. Nelson·Franz X. Kärtner
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Abstract

We analytically show how a superposition of beamlets produces terahertz radiation with greater spatial homogeneity and efficiency compared to tilted-pulse-fronts generated by diffraction gratings. The advantages are particularly notable for large pump bandwiths and beam sizes, alluding to better performance in the presence of cascading effects and higher energy pumping. A theory of terahertz generation using a superposition of beamlets is developed. It is shown how such an arrangement produces a distortion free tilted-pulse-front. Closed form expressions for terahertz spectra and transients in three spatial dimensions are derived. Conditions for obtaining performance parity and bounds for optimal parameters are furnished.

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Koustuban Ravi, Benjamin Ofori-Okai, Keith A. Nelson, Franz X. Kärtner. 2018-10-22. Terahertz generation by beamlet superposition. https://doi.org/10.1364/oe.27.026547

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