导引场下电磁泵浦自由电子激光的非线性理论

本文以Vlasov-Maxwell方程组为基础,用非线性动力学理论研究了存在导引场情况下电磁波泵浦的自由电子激光器的作用机制,导出了线性及非线性色散关系式,求出了非线性不稳定性增长率和自由电子激光的能量转换效率.结果表明,只要合理地选择参量条件,附加导引场可以大大提高自由电子激光的增长率和能量转换效率.

Nonlinear theory of an electromagnetically pumped free-electron laser with a guide magnetic field

A nonlinear analysis is presented for a free-electron laser with an electromagnetic pump in the presence of a guide magnetic field bu using kinetic theory based on the Vlasov-Maxwell equations. Linear and nonlinear dispersion relations are derived. The nonlinear growth rates of the free-electron laser are obtained for the weak and strong pump limits. Then according to the electron trapping mechanism the energy conversion efficiency is calculated. The results show that the guide magnetic field may lead to substantial enhancements in the growth rates and efficiency as long as reasonable parameters are chosen.