Ion separation in a Paul trap in the presence of damping force

Abstract

Dynamical behavior of particles in a Paul trap has been investigated by solving the set of differential equations considering the effect of damping force. Positions of the trapped ions as a function of time, ion trajectories and the phase space curves in the first stability region have been obtained in the presence of the damping force. The region of stability for r and z components as well as the first stability region with and without the damping force have been computed using the fourth-order Runge-Kutta method. Furthermore, for a Paul trap with specified dimensions and a typical RF frequency, the first stability region for 3H+ and 1H+ ions has been determined in the Vdc – Vac plane. It is worthwhile to note that computation of the stability region in the presence of damping force through the use of this method has been reported for the first time.

Keywords

• Paul trap
• damping force
• fourth-order Runge-Kutta method
• Mathieu equation
• stability region