High-speed radiography of laser-induced shock wave generation in a mock explosive.

Short-pulse laser-induced shock waves can produce high-pressure, short-duration mechanical loading in granular energetic media. To quantify this phenomenon, we performed experiments in a standard mock explosive -compressed sucrose- avoiding the handling constraints of explosives. Because the medium is granular and optically opaque, we employed time-resolved synchrotron X-ray imaging to directly observe shock-induced structural evolution. A green nanosecond laser pulse serves as the shock driver. The generation of a shock wave is confirmed by ex-situ tomographic analysis, which also enables quantitative interpretation of the time-resolved data to determine the shock pressure (~ 3.6 GPa) and propagation velocity (~ Mach 4). Furthermore, doping with aluminum nanoparticles enhances laser absorption and increases the resulting shock pressure. These results demonstrate the potential of high-power laser pulses for initiation of detonation in secondary explosives and provide a pathway toward faster, optically-triggered detonator concepts.