Cyclotron electron beam excited surface plasmon polaritons coherent radiation

Here the cyclotron electron beam (CEB) excitation of surface plasmon polaritons (SPPs) on the circular cylindrical structures is used to replace the linearly moving electron beam excitations. We have found that this change leads to essential consequence in physics for that there is natural periodicity of 2π in both circular cylindrical structure and CEB, and the combination of this dual natural periodicity not only make the excited SPPs transformation possible, but also bring many significant excellences to the mechanism.