  We report on experimental observations of formation and evolution of
transient plasma produced in fused silica glass with spatiotemporally focused
(STF) femtosecond laser pulses using a pump-probe shadow imaging technique.
Surprisingly, the observation shows that the track of the plasma is
significantly curved, which is attributed to an asymmetric density distribution
of the transient plasma produced in the focal volume caused by the pulse front
tilt of the STF laser field.
