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arXiv · 2512.24883

Probing quantum-coherent dynamics with free electrons

H. B. Crispin·N. Talebi
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Abstract

Recent advances in time-resolved cathodoluminescence have enabled ultrafast studies of single emitters in quantum materials with femtosecond temporal resolution. Here, we develop a quantum theory modeling the dynamics of free electrons interacting with quantum emitters in arbitrary initial states. Our analysis reveals that a free electron can induce transient coherent oscillations in the populations when the system is initially prepared in a coherent superposition of its states. Moreover, the electron energy spectrum exhibits a clear signature of the quantum coherence and sensitivity to the transition frequency of the emitter. These coherence effects manifest themselves as oscillations in the zero-loss peak of the spectral energy-loss probability. Our findings pave the way for characterization of quantum-coherent dynamics of individual quantum emitters by electron-probes.

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H. B. Crispin, N. Talebi. 2025-12-31. Probing quantum-coherent dynamics with free electrons. https://arxiv.org/abs/2512.24883

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