ANALYTICAL RESEARCH OF MODE LOCKING IN AN INFRARED SHORT-PULSE FREE-ELECTRON LASER

This paper has made an analytical research of mode locking in a kind of free electron laser （FEL）, given the condition of mode locking in the FEL and obtained that due to mode coupling the number of active cavity modes will be reduced by a factor of m_c, the low gain will be increased by a factor of m_c, the rate of the exponential growth will be increased by a factor of m_c¹/3, m_c is a ratio of the repetition frequency of the electron beam micropulses and the frequency interval of the cavity modes, m_c=△v_r/△v_c.