Dynamic microcavity arrays from colliding attosecond pulses in a medium

We predict a novel, to our knowledge, phenomenon-the formation of arrays of localized dynamic microcavities during asymmetric collision of single-cycle optical pulses in a two-level medium. We demonstrate that such pulses, behaving similarly to 2π self-induced transparency solitons, generate dynamic structures whose shape is determined by the time delay between the pulses. The obtained results open new avenues for sub-wavelength light field control and can be applied in the development of ultrafast optical devices, topological photonics, and petahertz electronics.