Physicists Capture Real-Time Quantum Leaps Across Energy Gaps in Graphene

REGENSBURG, Germany - Physicists from the University of Regensburg, Philipps-Universität Marburg, and Forschungszentrum Jülich successfully captured real-time video of electrons leaping across forbidden energy gaps in graphene with a transition probability reaching 100%. What happened? Using ultra-pure graphene and photoemission momentum microscopy, researchers directly observed Landau-Zener-Majorana transitions driven by intense light pulses. The study, published in Nature, reveals how strong electric fields accelerate electrons, allowing them to bypass forbidden energy bands without occupying intermediate energy states. "If you want to know who has won a race, you have to watch all participants," first author Vincent Eggers said, according to Wiley Analytical Science. The momentum microscope tracked electron velocities across the material's energy landscape at subcycle timescales. Why does it matter? The experiments demonstrate that quantum transition probabilities depend on how rapidly electrons encounter the energy gap rather than classical spatial tunneling barriers. Under strong optical fields, electrons bridged the gap with complete 100% tunneling efficiency, confirming theoretical predictions of non-adiabatic quantum dynamics. "Our experiment opens a panoramic window into the quantum world. Now, we can follow in real time how electrons move through the energy landscape of a material," co-author Giacomo Inzani told ScienceDaily. Controlling electrons via optical oscillations rather than electrical voltages establishes a technical foundation for petahertz-scale lightwave electronics. What comes next? The research consortium plans to apply its ultrafast momentum microscopy platform across additional quantum materials, including topological insulators and twisted van der Waals heterostructures. Physicists will map how electron-phonon lattice scattering disrupts coherent electron motion, establishing operational benchmarks for developing all-optical computing switches operating billions of times faster than current silicon microprocessors.