Compton Scattering Driven by Quantum Light

Abstract

Compton scattering is one of the cornerstones of quantum physics, describing the fundamental interaction of a charged particle with photons. The Compton effect and its inverse are utilized in experiments driving free electrons by high intensity lasers to create trains of attosecond X-ray pulses. So far, all theory and experiments of the Compton effect and its generalizations have relied on electromagnetic fields that can be described classically. Advances in the generation of intense squeezed light could enable driving the Compton effect with non-classical light. This outlook motivates exploring the role of photon statistics in the Compton effect. We develop a framework to describe the full non-perturbative interaction of a charged particle with a driving field ascribed with an arbitrary quantum light state. We obtain analytical results for the Compton emission spectrum when driven by thermal and squeezed vacuum states, showing a noticeable broadening of the emission spectrum relative to a classical (coherent state) drive, thus reaching higher emission frequencies for the same average intensity. We envision utilizing the quantum properties of light, including photon statistics, squeezing, and entanglement, as novel degrees of freedom to control the wide range of radiation phenomena at the foundations of quantum electrodynamics.