Subfemtosecond charge driving with correlation-assisted band engineering in a wide-gap semiconductor

First-principles calculations indicate that, before falling into dielectric breakdown, charge transport induced by a strong-intensity few-cycle optical waveform in the subfemtosecond time domain can be precisely controlled depending on band distortion engineered by strain along the [0001] direction in wurtzite-AlN. It is further discovered from a model of electron-hole interaction that the subfemtosecond charge driving with band engineering can be substantially strengthened by excitonic correlation and dynamics. With these findings, we reveal band engineering to be a route to the ultrafast charge control of semiconductors and indeed suggest an unexplored prototype of solid-state petahertz (1015Hz) device.