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arXiv · 2506.03460

Three-dimensional reconstruction of THz near-fields from a LiNbO$_3$ optical rectification source

Annika E. Gabriel Mohamed A. K. Othman·Patrick L. Kramer·Harumy Miura·Matthias C. Hoffmann·Emilio A. Nanni
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Abstract

Terahertz (THz) generation by optical rectification in LiNbO$_3$ (LN) is a widely used technique for generating intense THz radiation. The spatiotemporal characterization of THz pulses from these sources is currently limited to far-field methods. While simulations of tilted pulse front THz generation have been published, little work has been done to measure the near-field properties of the THz source. A better understanding of the THz near-field properties will improve optimization of THz generation efficiency, transport, and coupling. We demonstrate a technique for quantitative spatiotemporal characterization of single-cycle strong-field THz pulses with 2D near-field electro-optic imaging. We have reconstructed the full temporal 3D THz near-field and shown how the phase front can be tailored by controlling the incident pump pulse.

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Annika E. Gabriel Mohamed A. K. Othman, Patrick L. Kramer, Harumy Miura, Matthias C. Hoffmann, Emilio A. Nanni. 2025-06-03. Three-dimensional reconstruction of THz near-fields from a LiNbO$_3$ optical rectification source. https://arxiv.org/abs/2506.03460

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