Relativistic harmonic generation excited in the ultrashort laser pulse regime

The envelope equations describing the relativistic harmonic components are derived and used to analyze the third relativistic harmonic radiation in the short laser pulse regime. The results show that the pulse duration of the incident laser is an important parameter for the relativistic harmonic radiation and the harmonic radiation depends on the pumping laser pulse shape. The relativistic harmonic radiation is more efficient in the short laser pulse regime than in the long laser pulse regime. (C) 1996 American Institute of Physics.