An Integrated Velocity Profile Measurement from Nanosecond Pulse Laser-Driven Mini-Flyer to Shocked Sample

It is very important to develop a high time and space resolved velocity diagnostic technique for laser-driven shock wave experiments. However, it is still a difficult problem because of the limited size of laser-launched mini-flyer and ultra-short loading time in shocked sample. Thus, a micro focus Doppler pins system with time resolution of 50 ps and spatial resolution of 200 mm has been developed in our nanosecond laser-driven shock wave experiments, to perform an integrated velocity profile measurement from laser driven mini-flyer to impacted sample. The measured particle velocity of Z-cut quartz sample is 1.27 km/s while the impact velocity of 6 m thick Al foil flyer is 2.48 km/s, which is in agreement with the calculated Hugoniot results. This validates our technique. Using our technique, the experimental results for three different types of mini-flyers show that the substrate/deposit layer/silicone oil/Al foil flyer structure has higher laser energy coupling efficiency and better integrity. This is valuable for designing a laser-driven shock wave experimental assembly. These results indicate that our technique is a viable approach for studying dynamics of laser-driven shock wave in materials.