The objective of our research is to study ultrafast phenomena in correlated electron systems excited with femtosecond optical pulses, and to apply and develop new real-time spectroscopic techniques for studying real-time dynamics of elementary and collective excitations in these technologically important materials. The focus of the proposed research will be - but not limited to - on ultrafast studies of carrier, structural and collective mode dynamics in superconductors, low dimensional charge and spin density wave compounds, and the investigation of transient photo-doping effects in cuprates (or more broadly Mott insulators). The main idea of the proposed research is to determine the coupling strengths between various degrees of freedom (spin, electron, and lattice) in these materials and to determine the characteristic timescales of the phenomena as the important parameter for application of these materials in electronics. The proposed experiments may lead to the identification of the pairing mechanism in cuprate superconductors, hence solving one of the key mysteries of modern condensed matter physics.
