Direct laser field electron generation using a tight focused high intensity laser pulse

Energetic electrons generation (around 20 keV) by longitudinal field acceleration from a laser pulse has been demonstrated by focusing a radially polarized TM01 ultrashort laser pulse (1,8 microns, 550 microJ, 15 fs) with a high numerical aperture parabola. We extend this technique using a 100 TW laser system. The expected intensity is around 10E22 W/cm2. Preliminary results about energetic electrons generation (MeV range) by focusing a linearly polarized TEM00 ultrashort pulse (800 nm, 3 J, 30 fs) are presented.