%0 Journal Article %A M. Zahedian and B. Maraghechi and M. H. Rouhani %D 2011 %J International Journal of Physical and Mathematical Sciences %B World Academy of Science, Engineering and Technology %I Open Science Index 54, 2011 %T Nonlinear Simulation of Harmonically Coupled Two-Beam Free-Electron Laser %U https://publications.waset.org/pdf/14585 %V 54 %X A nonlinear model of two-beam free-electron laser (FEL) in the absence of slippage is presented. The two beams are assumed to be cold with different energies and the fundamental resonance of the higher energy beam is at the third harmonic of lower energy beam. By using Maxwell-s equations and full Lorentz force equations of motion for the electron beams, coupled differential equations are derived and solved numerically by the fourth order Runge–Kutta method. In this method a considerable growth of third harmonic electromagnetic field in the XUV and X-ray regions is predicted. %P 895 - 898