  The dynamics of electrons and atoms interacting with intense and ultrashort
optical pulses presents an important problem in physics that cuts across
different materials such as semiconductors and metals. The currently available
laser pulses, as short as 5 fs, provide a time resolution shorter than the
dephasing and relaxation times in many materials. This allows for a systematic
study of many-body effects using nonlinear optical spectroscopy. In this review
article, we discuss the role of Coulomb correlations in the ultrafast dynamics
of modulation-doped quantum wells and metal nanoparticles. We focus in
particular on the manifestations of non-Markovian memory effects induced by
strong electron-hole and electron-plasmon correlations.
