  We studied the excitation process of silicon under an intense double pulse.
We employed the three-temperature (electron, hole, and lattice) model (3TM)
together with Maxwell's equations. We solved Maxwell's equations by the
finite-difference time-domain approach. The lattice temperature and absorbed
energy at the surface increase significantly when the two laser pulses overlap
with constructive interference. On the other hand, destructive interference
substantially reduces the efficiency of laser excitation. On average, the
overlapped double pulse increases the efficiency to about twice the distinct
two-pulse case.
