Measuring the charge on single particles by laser-excited resonances in plasma crystals

Abstract

Experiments on the excitation of vertical particle resonances by laser radiation pressure are presented. The vertical resonance is used for the measurement of the charge on particles forming plasma crystals. The laser excitation technique allows us to excite the vertical resonance of a single particle in the plasma trap, whereas in earlier experiments the entire plasma crystal was excited to vertical oscillations. From the close agreement of both resonance techniques the earlier values of the dust charge are reconfirmed.