Nature · 2026
Abstract Strong light fields have unlocked entirely new possibilities to tailor coherent electron trajectories, engineer band structures and shape emergent phases of matter all-optically 1–9 . Unravelling the underlying quantum mechanisms requires a visualization of the lightwave-driven electron motion 10,11 directly in the band structure. Although photoelectron momentum microscopy has imaged photoexcited electrons averaged over many cycles of light 12–19 , subcycle band-structure videography has been limited to small electron momenta 8,20 . Yet, lightwave-driven elementary processes in quantum materials often occur throughout momentum space. Here we introduce attosecond-precision, subcycle band-structure videography covering the entire first Brillouin zone and visualize one of the most fundamental but elusive strong-field processes: non-adiabatic Landau–Zener–Majorana tunnelling. The interplay of strong-field-driven acceleration within the Dirac-like band structure of graphene and periodic Landau–Zener–Majorana interband tunnelling manifests in a coherent subcycle displacement and distortion of the carrier distribution at the Brillouin zone edge. The extremely non-thermal electron distributions also allow us to disentangle competing scattering processes and assess their impact on coherent electronic control. Our panoramic view of field-driven electron motion enables a new quality of microscopic understanding of strong-field control of quantum materials.
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