We present 3-dimensional particle-in-cell simulations for ultra-intense pul
se-laser-irradiated plasmas. The self-excited process of large magnetic fie
lds is one of the problems in laser-plasma interactions and in inertial con
finement fusion. Weibel instability is known to be a microscopic instabilit
y that causes spontaneously growing transverse waves due to an anisotropic
temperature. Spontaneously generated large magnetic fields can be generated
by ultra-intense laser-irradiation-causing sources, such as anisotropic te
mperature. (C) 1999 Elsevier Science S.A. All rights reserved.