Femtosecond time-delay X-ray holography.
Extremely intense and ultrafast X-ray pulses from free-electron lasers offer unique opportunities to study fundamental aspects of complex transient phenomena in materials. Ultrafast time-resolved methods usually require highly synchronized pulses to initiate a transition and then probe it after a precisely defined time delay. In the X-ray regime, these methods are challenging because they require complex optical systems and diagnostics. Here we propose and apply a simple holographic measurement scheme, inspired by Newton's 'dusty mirror' experiment, to monitor the X-ray-induced explosion of microscopic objects. The sample is placed near an X-ray mirror; after the pulse traverses the sample, triggering the reaction, it is reflected back onto the sample by the mirror to probe this reaction. The delay is encoded in the resulting diffraction pattern to an accuracy of one femtosecond, and the structural change is holographically recorded with high resolution. We apply the technique to monitor the dynamics of polystyrene spheres in intense free-electron-laser pulses, and observe an explosion occurring well after the initial pulse. Our results support the notion that X-ray flash imaging can be used to achieve high resolution, beyond radiation damage limits for biological samples. With upcoming ultrafast X-ray sources we will be able to explore the three-dimensional dynamics of materials at the timescale of atomic motion.
University of California, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
Henry N
HN
Chapman
Stefan P
SP
Hau-Riege
Michael J
MJ
Bogan
Sasa
S
Bajt
Anton
A
Barty
Sébastien
S
Boutet
Stefano
S
Marchesini
Matthias
M
Frank
Bruce W
BW
Woods
W Henry
WH
Benner
Richard A
RA
London
Urs
U
Rohner
Abraham
A
Szöke
Eberhard
E
Spiller
Thomas
T
Möller
Christoph
C
Bostedt
David A
DA
Shapiro
Marion
M
Kuhlmann
Rolf
R
Treusch
Elke
E
Plönjes
Florian
F
Burmeister
Magnus
M
Bergh
Carl
C
Caleman
Gösta
G
Huldt
M Marvin
MM
Seibert
Janos
J
Hajdu
D004583:Electrons; D006696:Holography / Q000379:methods*; D007834:Lasers; D008863:Microspheres; D011137:Polystyrenes / Q000737:chemistry*; D013997:Time Factors; D014965:X-Rays
D011137:Polystyrenes