Quantum dance to the beat of a drum: Researchers observe how energy of single electron is tuned by surrounding atomsA discrete energy level of an atomic vacancy in an atomically thin material shifts upon excitation of a drum-like vibration. The temporal evolution of the localized energy level is intricately linked to the atomic excursions owing to the drum mode. Credit: Brad Baxley
The physicists used an atomically thin material to investigate how a discrete energy level changes when this atomic layer moves up and down like the membrane of a drum. They observed this at a vacancy—the void left behind when an individual atom is removed. "To track how an energy level shifts, it is necessary to take stroboscopic snapshots of the energy level, with each snapshot being recorded in less than a trillionth of a second, faster than picoseconds," explains first author Carmen Roelcke.
The work of the Regensburg team establishes a new era in the study of the dynamics of atomically localized energy levels and their interaction with the environment. This discovery enables the local control of discretein the most direct way. For instance, the motion of individual atoms could change the energy structure of a material and thus create new functionalities or specifically change the properties of light-emitting semiconductors and molecules.