For a single electron, a DC magnetic field is combined with an AC electric field. The frequency of the electric field is tuned near, but not equal to, the cyclotron frequency of the electron and the scattering time is set to be very long. Why does the electron initially spiral out? Why does it then spiral back in at a later time?
Increase the omega slider to 0.16 to increase the time between minima of the envelope. What value of omega is required to have the amplitude of response increase indefinitely? This is the cyclotron resonance frequency.