Self-evolving photonic crystals for ultrafast photonics

Ultrafast dynamics in nanophotonic materials is attracting increasing attention for both fundamental science and device functionality. Typically, such dynamics relies on external stimuli (optical pumping or voltage pulses), which become impractical at larger optical powers due to increased control energy. The authors demonstrate a self-evolving photonic crystal concept where the spatial profile of the photonic band dynamically changes through carrier–photon interactions under continuous uniform current injection. Using this approach, they experimentally realize short-pulse generation with peak power of 80 W and pulse width <30 ps in a 1-mm-diameter GaAs-based photonic crystal. These self-evolving carrier–photon dynamics broaden the potential of nanophotonic materials and enable diverse scientific and industrial applications.