"Towards Next-Generation X-Ray Imaging with Tunable X-Rays and Quantum Recoil" by Nanyang Assistant Prof Wong Liang Jie | IAS Discovery Science Seminar

Quantum recoil – the defiance of classical physics by photons spontaneously emitted from free electrons – is not only a fundamental phenomenon but also of direct importance to the practical development of versatile, compact, coherent X-ray sources. First postulated by Russian Physicist and Nobel Laureate Vitaly Ginzburg in 1940, quantum recoil has remained experimentally elusive.

In this talk, Nanyang Asst Prof Wong will discuss the quest for the holy grail of a versatile, compact X-ray source, and the promise of free-electron-driven van der Waals materials in achieving this goal. He will describe how the quest led his team surprisingly to an experimental demonstration of quantum recoil. Despite being a quantum phenomenon, quantum recoil is observable even at room temperature and in the presence of external scattering events. His team outlines plans to measure regimes where quantum recoil manifests strongly, resulting for example in the emission of a classically predicted X-ray photon as a very low energy photon. Their findings pave the way to safer and more discerning X-ray imaging technology that could be disruptive in a broad range of applications, from manufacturing inspection to medical imaging. 

Co-organisers: IAS NTU and the Graduate Students' Clubs of EEE, SCSE and SPMS