Experiments on the vortex dynamics in superfluid 4He with no normal component

We report results from ongoing experiments on the dynamics of quantized vortices in superfluid He-4 at temperatures below 0.2 K. Charged vortex rings of micron size were used to detect the presence of vortices, to create a turbulent tangle, and to charge an array of rectilinear vortex lines. The results reveal that the ion technique has great potential for the study of vortices in He-4 at very low temperatures.