Shock waves in dusty plasma

This thesis describes my research on laboratory dusty plasmas. This is a fascinating field of experimental research which appeared only 25 years ago. Micrometer-sized particles are immersed in ionized gas, and due to an electric charge, they can self-organize into a crystalline arrangement, which is very similar to crystals in molecular substances such as salt grains or ice. These dusty plasma crystals can be melted to form a liquid. What is fascinating about these crystal-like and liquid-like arrangements in a dusty plasma is that the individual particles can be seen by eye, and imaged by video camera, whereas in a molecular substance such as liquid water, the positions of individual molecules cannot be seen.

It is these unique properties of dusty plasma that made my research possible. I studied shock waves in crystalline and liquid dusty plasma, and I was able to measure the width of a shock, and I found that contrary to theory (which predicts an infinitesimally thin width), my shocks have a width that is not infinitesimal, but one that is large enough to measure. I found the width is comparable to the interparticle spacing. Such an experiment would be impossible with an ordinary molecular substance. My other results include a discovery of an unexpected energy input into the propagation of the shock wave as it travels through the substance. I have also introduced a new method of generating shocks in dusty plasma, which allows the production of both blast waves (like an explosion) and continuously-driven shock waves (like those produced by a supersonic jet).