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arXiv · 2212.13066

Low-velocity-favored transition radiation

Jialin Chen·Ruoxi Chen·Zheng Gong·Hao Hu·Yi Yang·Xinyan Zhang·Chan Wang·Ido Kaminer·Hongsheng Chen·Baile Zhang·Xiao Lin
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Abstract

When a charged particle penetrates through an optical interface, photon emissions emerge - a phenomenon known as transition radiation. Being paramount to fundamental physics, transition radiation has enabled many applications from high-energy particle identification to novel light sources. A rule of thumb in transition radiation is that the radiation intensity generally decreases with the particle velocity v; as a result, low-energy particles are not favored in practice. Here we find that there exist situations where transition radiation from particles with extremely low velocities (e.g. v/c<0.001) exhibits comparable intensity as that from high-energy particles (e.g. v/c=0.999), where c is light speed in free space. The comparable radiation intensity implies an extremely high photon extraction efficiency from low-energy particles, up to eight orders of magnitude larger than that from high-energy particles. This exotic phenomenon of low-velocity-favored transition radiation originates from the excitation of Ferrell-Berreman modes in epsilon-near-zero materials. Our findings may provide a promising route towards the design of integrated light sources based on low-energy electrons and specialized detectors for beyond-standard-model particles.

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Jialin Chen, Ruoxi Chen, Zheng Gong, Hao Hu, Yi Yang, Xinyan Zhang, Chan Wang, Ido Kaminer, Hongsheng Chen, Baile Zhang, Xiao Lin. 2022-12-26. Low-velocity-favored transition radiation. https://arxiv.org/abs/2212.13066

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