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arXiv · 2409.08391

Entangled two-photon absorption for the continuous generation of excited state populations in plasma

David R. Smith·Matthias Beuting·Daniel J. Den Hartog·Benedikt Geiger·Scott T. Sanders·Xuting Yang·Jennifer T. Choy
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Abstract

Entangled two-photon absorption (ETPA) may be a viable technique to continuously drive an excited state population in plasma for high-bandwidth spectroscopy measurements of localized plasma turbulence or impurity density. Classical two-photon absorption commonly requires a high-intensity, pulsed laser, but entangled photons with short entanglement time and high time correlation may allow for ETPA using a lower intensity, continuous-wave laser. Notably, ETPA with non-collinear entangled photon generation allows for cross-beam spatial localization of the absorption or fluorescence signal using a single laser source. Entangled photon generation, the ETPA cross-section, candidate transitions for an Ar-II species, and plans for a proof-of-principle measurement in a helicon plasma are discussed.

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David R. Smith, Matthias Beuting, Daniel J. Den Hartog, Benedikt Geiger, Scott T. Sanders, Xuting Yang, Jennifer T. Choy. 2024-09-12. Entangled two-photon absorption for the continuous generation of excited state populations in plasma. https://arxiv.org/abs/2409.08391

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