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arXiv · 2311.15070

Time-refraction and time-reflection above critical angle for total internal reflection

Lior Bar-Hillel·Alex Dikopoltsev·Amit Kam·Yonatan Sharabi·Ohad Segal·Eran Lustig·Mordechai Segev
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Abstract

We study the time-reflection and time-refraction of waves caused by a spatial interface with a medium undergoing a sudden temporal change in permittivity. We show that monochromatic waves are transformed into a pulse by the permittivity change, and that time-reflection is enhanced at the vicinity of the critical angle for total internal reflection. In this regime, we find that the evanescent field is transformed into a propagating pulse by the sudden change in permittivity. These effects display enhancement of the time-reflection and high sensitivity near the critical angle, paving the way to experiments on time-reflection and photonic time-crystals at optical frequencies

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Lior Bar-Hillel, Alex Dikopoltsev, Amit Kam, Yonatan Sharabi, Ohad Segal, Eran Lustig, Mordechai Segev. 2023-11-25. Time-refraction and time-reflection above critical angle for total internal reflection. https://arxiv.org/abs/2311.15070

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