The invention generally relates to ion traps and methods of use thereof. In certain embodiments, the invention provides a system that includes a mass spectrometer including an ion trap, and a central processing unit (CPU). The CPU has storage that is coupled to the CPU for storing instructions that when executed by the CPU cause the system to apply a constant radio frequency (RF) signal to the ion trap, and apply a first alternating current (AC) signal to the ion trap the frequency of which varies as a function of time.