Band-selective measurements of electron dynamics in VO2 using femtosecond near-edge x-ray absorption.
We report on the first demonstration of femtosecond x-ray absorption spectroscopy, made uniquely possible by the use of broadly tunable bending-magnet radiation from "laser-sliced" electron bunches within a synchrotron storage ring. We measure the femtosecond electronic rearrangements that occur during the photoinduced insulator-metal phase transition in VO2. Symmetry- and element-specific x-ray absorption from V2p and O1s core levels (near 500 eV) separately measures the filling dynamics of differently hybridized V3d-O2p electronic bands near the Fermi level.
Cavalleri
A
A
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA. a.cavalleri1@physics.ox.ac.uk
Rini
M
M
Chong
H H W
HH
Fourmaux
S
S
Glover
T E
TE
Heimann
P A
PA
Kieffer
J C
JC
Schoenlein
R W
RW