A static magnetic field is applied in the same direction using a first magnet and a second magnet. The magnetic field is applied to a gap of uniform thickness between the first and second magnets. Voltages are applied to three or more electrodes located in the gap using a switchable voltage source. The voltages are applied to create a static electric field perpendicular to the static magnetic field in an input channel and at least one channel of two or more output channels. The channels are defined by gaps between the three or more electrodes. The simultaneous application of the static magnetic field and the static electric field causes ions from an ion beam of a mass spectrometer to move into and through the input channel and through at least one channel of the two or more output channels to another location in the mass spectrometer.