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The Oscillating Paul Trap Potential

  To achieve ion confinement in a Paul trap, an oscillating electric potential difference, , is applied in place of or in addition to a static potential, :

The resultant Paul trap potential alternates between: (1) a focusing potential well in the axial direction with a defocusing inverted radial potential; and (2) a focusing potential well in the radial direction with a defocusing axial potential. By focusing particles in one direction and then in the other, the dynamic Paul trap potential creates a stable equilibrium whereas the static quadrupole potential was capable of only unstable equilibrium.gif

Wolfgang Christian
Fri May 12 10:36:01 EDT 1995