  We demonstrate pump-probe techniques, namely the Doppler spectrometry and the
reflectometry in detail, which directly capture the time-resolved ultrafast
evolution of high intensity femtosecond laser-driven hot, dense plasma. These
techniques are capable of capturing ultrafast plasma dynamics on time scales of
sub 100 femtosecond. We have shown the dynamics of high intensity femtosecond
laser-driven shock like disturbance into the plasma at densities more than
10^22/cc. This can help understanding the physics related to shock ignition,
supernova explosion and many other astrophysical scenarios and also can have
implications in medicine and chemistry. Furthermore, we have investigated the
ultrafast acoustic phenomena due to hydrodynamics inside an expanding hot,
dense plasma in its transient phase by the correlated measurements of Doppler
spectrometry and reflectometry.
