Terahertz Microscopy Through Complex Media

Vivek Kumar; Vittorio Cecconi; Antonio Cutrona; Luke Peters; Luana Olivieri; Juan S. Totero Gongora; Alessia Pasquazi; Marco Peccianti

arXiv · 2412.06427

Terahertz Microscopy Through Complex Media

Vivek Kumar·Vittorio Cecconi·Antonio Cutrona·Luke Peters·Luana Olivieri·Juan S. Totero Gongora·Alessia Pasquazi·Marco Peccianti

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Abstract

Manipulating broadband fields in scattering media is a modern challenge across photonics and other wave domains. Recent studies have shown that complex propagation in scattering media can be harnessed to manipulate broadband light wave packets in space-time for focusing, imaging, and computing applications. Interestingly, while many proposed methodologies operate on intensity-based assessment of scattered fields, often in the spectral domain, from a pure transmission-function perspective, scattering operates as a linear field-level combinatory process, i.e., the superposition of transformation of unit excitations. As a result, we recently demonstrated that gaining experimental access to instantaneous scattered fields, as available through time-domain spectroscopy in the terahertz spectral range, in conjunction with sparse light excitation typical of ghost imaging, provides a key advantage in enabling the functionalisation of scattering, exposing a novel modelling paradigm. In this paper, we provide experimental proof of reconstructing 1-dimensional object features through a scattering medium using a fully broadband time-domain terahertz approach.

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Vivek Kumar, Vittorio Cecconi, Antonio Cutrona, Luke Peters, Luana Olivieri, Juan S. Totero Gongora, Alessia Pasquazi, Marco Peccianti. 2024-12-09. Terahertz Microscopy Through Complex Media. https://arxiv.org/abs/2412.06427

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