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arXiv · 2311.15074

Upconversion of infrared light by graphitic micro-particles due to photo-induced structural modification

Rohin Sharma·Nishma Bhattarai·Rijan Maharjan·Lilia M. Woods·Nirajan Ojha·Ashim Dhakal
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Abstract

Recent reports of upconversion and white light emission from graphitic particles warrant an explanation of the physics behind the process. We offer a model, wherein the upconversion is facilitated by photo-induced electronic structure modification allowing for multi-photon processes. As per the prediction of the model, we experimentally show that graphite upconverts infrared light centered around 1.31~$\mu$m to broadband white light centered around 0.85 $\mu$m. Our results suggest that upconversion from shortwave infrared ($\sim$3~$\mu$m) to visible region may be possible. Our experiments show that the population dynamics of the electronic states involved in this upconversion process occur in the timescale of milliseconds.

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Rohin Sharma, Nishma Bhattarai, Rijan Maharjan, Lilia M. Woods, Nirajan Ojha, Ashim Dhakal. 2023-11-25. Upconversion of infrared light by graphitic micro-particles due to photo-induced structural modification. https://arxiv.org/abs/2311.15074

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