Revealing Quantum Properties of Radiation – 2D Interaction Takes Researchers by Surprise

Technion researchers present the first-ever observation of the Cherenkov radiation phenomenon in a two-dimensional space.

The researchers from the Andrew and Erna Viterbi Faculty of Electrical and Computer Engineering at the Technion – Israel Institute of Technology have presented the first-ever experimental observation of Cherenkov radiation confined within a two-dimensional space. The results were surprising, as they set a new record for electron-radiation coupling strength and revealed the quantum properties of the radiation.

Cherenkov radiation is a unique physical phenomenon that has been utilized for a number of years in medical imaging, particle detection, and laser-driven electron accelerators. The researchers from Technion linked this phenomenon to potential future applications in photonic quantum computing and free-electron quantum light sources.

The study, which was published in Physical Review X, was headed by Ph.D. students Yuval Adiv and Shai Tsesses from the Technion, together with Hao Hu from the Nanyang Technological University in Singapore (now a professor at Nanjing university in China). It was supervised by Prof. Ido Kaminer and Prof. Guy Bartal of the Technion, in collaboration with colleagues from China: Prof. Hongsheng Chen, and Prof. Xiao Lin from Zhejiang University.

The interaction of free electrons with light underlies a plethora of known radiation phenomena and has led to numerous applications in science and industry. One of the most important of these interaction effects is the Cherenkov radiation – electromagnetic radiation emitted when a charged particle, such as an electron, travels through a medium at a speed greater than the phase velocity of light in that specific medium.

It is the optical equivalent of a supersonic boom, which occurs, for example, when a jet travels faster than the speed of sound. Consequently, Cherenkov radiation is sometimes called an “optical shock wave.” The phenomenon was discovered in 1934. In 1958, the scientists who discovered it were awarded the Nobel Prize in Physics.