Experiments with single electrons in liquid helium

Abstract

We have developed an apparatus which can be used to make movies showing the motion of individual electrons in liquid helium. A sound wave is used to explode an electron bubble for a fraction of a microsecond and to make it grow to have a radius of around 10 microns. While the bubble has this large size it is illuminated with a flash lamp and its position recorded. We report on a number of interesting phenomena that have been observed in these experiments. Some electrons that first appear near the surface of the transducer are likely to be produced as a result of cosmic rays passing through the liquid in the experimental cell. We discuss the details of this process © 2009 IOP Publishing Ltd.