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Rotating-radio-frequency ion traps



T Hasegawa, John J. Bollinger


We propose a new ion trap, the rotating-rf trap, in which motion of a charged particle is described not by Mathieu-type functions but by trigonometric functions. In the rotating-rf trap, a quadrupole electric field confines charged particles, whereas in a normal rf trap, an oscillating quadrupole field does. Ion motion in a rotating-rf trap is a superposition of two non-degenerate circular motions and two corresponding circular micromotions. The cases of applying a uniform magnetic field and a quadrupole dc electric field in addition to the rotating rf field are also discussed. Confinement in a rotating field can be tighter than in a normal linear rf trap with the same experimental parameter values.
Physical Review A (Atomic, Molecular and Optical Physics)


ion traps, mass spectroscopy, Mathieu functions, micromotion, Paul traps, rf traps, rotating rf traps, secular motion, stability diagram


Hasegawa, T. and Bollinger, J. (2005), Rotating-radio-frequency ion traps, Physical Review A (Atomic, Molecular and Optical Physics), [online], (Accessed June 13, 2024)


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Created October 20, 2005, Updated January 27, 2020