Low-Velocity-Favored Transition Radiation

Jialin Chen; Ruoxi Chen; Fuyang Tay; Zheng Gong; Hao Hu; Yi Yang; Xinyan Zhang; Chan Wang; Ido Kaminer; Hongsheng Chen; Baile Zhang; Xiao Lin

doi:10.1103/PhysRevLett.131.113002

Low-Velocity-Favored Transition Radiation

Phys Rev Lett. 2023 Sep 15;131(11):113002. doi: 10.1103/PhysRevLett.131.113002.

Authors

Jialin Chen^{1

2

3}, Ruoxi Chen^{1

2}, Fuyang Tay^{4

5}, Zheng Gong^{1

2}, Hao Hu⁶, Yi Yang⁷, Xinyan Zhang^{1

2}, Chan Wang^{1

2

8}, Ido Kaminer³, Hongsheng Chen^{1

2

8

9}, Baile Zhang^{10

11}, Xiao Lin^{1

2}

Affiliations

¹ Interdisciplinary Center for Quantum Information, State Key Laboratory of Extreme Photonics and Instrumentation, ZJU-Hangzhou Global Scientific and Technological Innovation Center, College of Information Science & Electronic Engineering, Zhejiang University, Hangzhou 310027, China.
² International Joint Innovation Center, the Electromagnetics Academy at Zhejiang University, Zhejiang University, Haining 314400, China.
³ Department of Electrical and Computer Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
⁴ Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA.
⁵ Applied Physics Graduate Program, Smalley-Curl Institute, Rice University, Houston, Texas 77005, USA.
⁶ School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
⁷ Department of Physics, University of Hong Kong, Hong Kong 999077, China.
⁸ Key Lab of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang, Jinhua Institute of Zhejiang University, Zhejiang University, Jinhua 321099, China.
⁹ Shaoxing Institute of Zhejiang University, Zhejiang University, Shaoxing 312000, China.
¹⁰ Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
¹¹ Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637371, Singapore.

PMID: 37774266
DOI: 10.1103/PhysRevLett.131.113002

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 decrease of 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<10^{-3}) exhibits comparable intensity as that from high-energy particles (e.g., v/c=0.999), where c is the light speed in free space. The comparable radiation intensity implies an extremely high photon extraction efficiency from low-energy particles, up to 8 orders of magnitude larger than that from high-energy particles. This exotic phenomenon of low-velocity-favored transition radiation originates from the interference of the excited Ferrell-Berreman modes in an ultrathin epsilon-near-zero slab. Our findings may provide a promising route toward the design of integrated light sources based on low-energy electrons and specialized detectors for beyond-standard-model particles.