Transient strain driven by a dense electron-hole plasma.
We measure transient strain in ultrafast laser-excited Ge by time-resolved x-ray anomalous transmission. The development of the coherent strain pulse is dominated by rapid ambipolar diffusion. This pulse extends considerably longer than the laser penetration depth because the plasma initially propagates faster than the acoustic modes. X-ray diffraction simulations are in agreement with the observed dynamics.
DeCamp
M F
MF
FOCUS Center and Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Reis
D A
DA
Cavalieri
A
A
Bucksbaum
P H
PH
Clarke
R
R
Merlin
R
R
Dufresne
E M
EM
Arms
D A
DA
Lindenberg
A M
AM
MacPhee
A G
AG
Chang
Z
Z
Lings
B
B
Wark
J S
JS
Fahy
S
S