On Coherent Delocalization in the Light-Matter Interaction

Understand

We investigate how the coherent spreading of the center of mass wave function of a particle, such as an atom, molecule or ion, affects the particle's interaction with fields such as the electromagnetic field or a phonon field, in view also of possible applications to emerging quantum technologies.

• To this end, we develop a suitably generalized Unruh-deWitt model for the interaction between a delocalizing first quantized particle and a second quantized field.
• We study how the coherent spreading of the center of mass wave function of the particle affects emission and absorption rates and we find, in particular, that in the case of a supersonic coherent spreading in a medium, there should occur Cherenkov-like emissions, along with the excitation of the particle.