Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids.
A linear accelerator based source of coherent radiation, FLASH (Free-electron LASer in Hamburg) provides ultra-intense femtosecond radiation pulses at wavelengths from the extreme ultraviolet (XUV; lambda<100nm) to the soft X-ray (SXR; lambda<30nm) spectral regions. 25-fs pulses of 32-nm FLASH radiation were used to determine the ablation parameters of PMMA - poly (methyl methacrylate). Under these irradiation conditions the attenuation length and ablation threshold were found to be (56.9+/-7.5) nm and approximately 2 mJ*cm(-2), respectively. For a second wavelength of 21.7 nm, the PMMA ablation was utilized to image the transverse intensity distribution within the focused beam at mum resolution by a method developed here.
Chalupský
J
J
Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic. chal@fzu.cz
Juha
L
L
Kuba
J
J
Cihelka
J
J
Hájková
V
V
Koptyaev
S
S
Krása
J
J
Velyhan
A
A
Bergh
M
M
Caleman
C
C
Hajdu
J
J
Bionta
R M
RM
Chapman
H
H
Hau-Riege
S P
SP
London
R A
RA
Jurek
M
M
Krzywinski
J
J
Nietubyc
R
R
Pelka
J B
JB
Sobierajski
R
R
Meyer-Ter-Vehn
J
J
Tronnier
A
A
Sokolowski-Tinten
K
K
Stojanovic
N
N
Tiedtke
K
K
Toleikis
S
S
Tschentscher
T
T
Wabnitz
H
H
Zastrau
U
U