Ion Trapping Glass Microspheres
Our masters student Manish alongside post-doc James Millen have built a quadrupole ion-trap which uses alternating electric fields to produce a potential well (like a deep valley) that traps charged particles.
It really is a beautiful design but very small and delicate.
High voltages (>1000 V) are needed but we can now trap 10 micron diameter silica spheres!
Here is a video we recorded where we overload the ion trap with loads of glass microspheres. Because their charged surfaces repel one another, they form this semi-stable trace of the trapping field potential (like magnetic lines around a magnet!).