Brillouin enhanced four-wave mixing and phase conjugation of electroma
gnetic waves in weakly collisional fully ionized plasmas are considere
d. It is found that the nonlinearity associated with the nonlocal elec
tron heat transport may dominate over the ponderomotive force and cons
equently there might appear an enhanced degenerate four-wave mixing an
d phase conjugation reflectivity. (C) 1998 American Institute of Physi
cs.