A preprint can be downloaded here. Other articles on this work appear in Science News, New Scientist, Phyiscs News Update, and Nature.

Schematic of a shock wave moving to the right which compresses the lattice by a factor of two. Light incident from the right (red arrow) will be converted up in frequency at the shock front and escape to the right. The black arrows indicate the adiabatic evolution of the modes for the lowest two bands.

Large frequency shift across the bandgap. Depicted are four moments in time during a computer simulation of a shock moving to the right. The shock front location is indicated by the dotted green line. The light begins the simulation below the gap in the unshocked material as in the schematic above. As the light propagates to the left, most of it is trapped at the shock front until it escapes to the right at a much higher frequency.

This is a movie of the simulation in the figure above, with the same axes. The shock propagates through three lattice units, and three pulses are upconverted. Click here for a larger version (17.5 MB).

Bandwidth narrowing. Depicted are two moments in time during computer simulation of the shock. The shock front is indicated by the dotted green line. Light is confined between the reflecting shock front on the left and a fixed reflecting surface on the right. As the shock moves to the right, the bandwidth of the confined light is decreased by a factor of 4.