Sub Femtosecond K-Shell Excitation Using Carrier Envelop Phase
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Transcript Sub Femtosecond K-Shell Excitation Using Carrier Envelop Phase
Sub femtosecond K-shell excitation using
Carrier Envelop Phase Stabilized 2-Cycles IR
(2.1m) Radiation Source.
Gilad Marcus
The Department of Applied Physics, Hebrew University,Jerusalem, Israel
FRISNO 12, Ein Gedi 2013
Acknowledgment
• Reinhard Kienberger 1
Wolfram Helml 1
• Ferenc Krausz 1
• Robert Hartmann 2
• Takayoshi Kobayashi
3
Xun Gu 1
• Lothar Strueder 4
Yunpei Deng 1
1.
2.
3.
4.
Max Planck, Quantum Optic, Germany
pnSensor GmbH, Germany
University of Electro-Communications, Chofu, Tokyo,
Japan
Max Planck, Extraterrestrial Physics, Germany
Outlines
Introduction (defining the goal)
The IR OPCPA system
keV high harmonics
High Harmonics the 3 steps model
TL
plateau
cut-off
tx
uv
max Wkin 3.17U p ,
Up
eE
2
4meL2
I2
Re-collision Processes
High harmonics spectra
High Harmonics
Discrete electron spectrum
Elastic scattering
Double ionization /
excitation
Motivation for keV HHG
•
Currently, the photon energy of atto-second
pulses is limited to ~150 eV ( ~8 nm).
Pushing the HHG toward the x-ray regime
Shorter attosecond pulses
Access to the water-window (300-500 eV)
Time resolved spectroscopy of inner-shell processes
X-ray diffraction imaging with a better resolution
Re-colliding electrons with higher energies
Laser induced diffraction imaging with better time and
space resolution (elastic scattering)
Efficient Inner-shell excitation (inelastic scattering)
Pushing atto-tools toward higher energies
by using a longer wavelength
I
0.15
(PW/cm2)
Ion yield of Xe vs. Laser intensity
0.5
1.0
λ (nm)
800 2100 800
2100 800
2100
Up (eV)
9.0
61.8 30
206
60
412
ħωmax
(eV)
44
211
668
205
1321
110
U p I2
Few-cycles Pulse
Recombination emission:
soft-X-ray photon emission upon
the electron recombining into its
ground state
Emission of
highest-energy
photon
E f (t )cos t CEP
Ionization
threshold
Cosine waveform
Few-cycles Pulse
Recombination emission:
soft-X-ray photon emission upon the
electron recombining into its ground
state
Emission of
highest-energy
photons
E f (t ) cos t
2
Ionization
threshold
Sine waveform
Self CEP Stabilization
The 2-cycles IR source
m
n
15 fsec
740 µJ
1 kHz
wavelength, nm
2 cycles IR (2.1m) source
f-to-3f interferogram
OPA system output:
Carrier wave-length:
Pulse duration:
Pulse energy:
Rep rate:
2.1m
15.7 fs (2 cycles)
0.7 mJ
1000 Hz
Automatically Carrier-envelope-phasestabilized
Long term (few hours) phase scan
B.Bergues, et. al, New Journal of Physics 13, no. 6 ( 2011): 063010.
I. Znakovskaya, et al. PRL 108, no. 6 (2012): 063002.
keV high harmonics and K-shell excitation
focusing lens
(CaF2, 250 mm)
Ne/N2 gas target,
pressure up to 3 bar!
PN
Camera
THG
THG FROG
FROG
Diagnostics for pulse
compression measurement
compressor
(bulk silicon)
High harmonic beam from N2
through 150nm Pd +500nm C
keV high harmonics and K-shell excitation
focusing lens
(CaF2, 250 mm)
Ne/N2 gas target,
pressure up to 3 bar!
PN
Camera
THG
THG FROG
FROG
Diagnostics for pulse
compression measurement
compressor
(bulk silicon)
High harmonic beam from N2
through 150nm Pd +500nm C
keV high harmonics and K-shell excitation
count / bin
High harmonics spectrum
from a neon gas target
through 500nm aluminum
10
HHG (Ne)
T (3bar Ne)
T (500nm Al)
4
10
3
10
10
-2
1
10
10
-1
2
10
10
0
-3
0
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
photons energy [eV]
Vanadium L-edge
60
Iron L-edge
0.4
(a)
60
50
0.7
(b)
50
0.6
40
0.5
0.2
30
20
0.4
30
0.3
20
0.2
0.1
10
0
10
500
1000
1500
photons energy [eV]
0
0
0.1
500
1000
1500
photons energy [eV]
0
transmission
transmission
40
counts
counts / bin
bin
Same spectrum through
additional 500nm of
vanadium (a) or iron (b)
counts
counts / bin
bin
0.3
transmission
10
keV high harmonics and K-shell excitation
counts / bin
10
10
10
10
8
6
Ne K-edge
10
Spectrum from N2 Target
Spectrum from Ne Target
counts / bin
10
4
10
10
10
10
6
Nitrogen
K-edge
4
2
2
0
500
1000
photons energy [eV]
1500
100
200
300
400
500
photons energy [eV]
600
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Better phase matching conditions
due to the absorption lines
1
Re(n)
Im(n)
0.5
0
0.5
1
/
1.5
0
Inner shell excitation followed
by x-ray fluorescence
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Calculation shows: Plasma
dispersion still dominate
1
Re(n)
Im(n)
0.5
0
0.5
1
/
1.5
0
Inner shell excitation followed
by x-ray fluorescence
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Inner shell excitation followed
by x-ray fluorescence
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Pex (ti ) / D 2 (ti )dt
av A
Pex dt
S
ab
fL
rad
d
1 exp 0 ab L
Au
4
Inner shell excitation followed
by x-ray fluorescence
- in-elastic excitation cross section
D - electron wave packed radius
- ionization rate
0 - gas density
rad , Au - dacay rates (radiation , Auger)
2D
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Pex (ti ) / D 2 (ti )dt
av A
Pex dt
S
fL
ab
rad
d
1 exp 0 ab L
Au
4
Inner shell excitation followed
by x-ray fluorescence
180
photon yield [counts / sec]
80
photon yield
64
48
32
16
0
0
1
2
3
pressure [bar]
4
160
140
120
100
80
2D
60
40
20
0
0
1
2
3
pressure [bar]
4
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Pex (ti ) / D 2 (ti )dt
av A
Pex dt
S
ab
fL
rad
d
1 exp 0 ab L
Au
4
Inner shell excitation followed
by x-ray fluorescence
180
photon yield [counts / sec]
80
photon yield
64
48
32
16
0
0
1
2
3
pressure [bar]
4
160
140
120
100
80
2D
60
40
20
0
0
1
2
3
pressure [bar]
4
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Pex (ti ) (ti )dt 0 (v)v(t )dt
av A
Pex dt
ti
S
fL
ab
rad
d
1 exp 0 ab L
Au
4
Inner shell excitation followed
by x-ray fluorescence
80
photon
yield
photon yield
150
64
48
100
32
photon yield [counts / sec]
180
4
2
0
0
2
4
16
50
0
0
0
10.5
2
1
3
pressure [bar]
1.5
4
160
140
120
100
2
80
2D
60
40
20
0
0
2.5
pressure [bar]
1
32
3
3.5
pressure [bar]
44
keV high harmonics and K-shell excitation
Enhanced peak at the K-edge
Pex (ti ) (ti )dt 0 (v)v(t )dt
av A
Pex dt
ti
S
fL
ab
rad
d
1 exp 0 ab L
Au
4
Inner shell excitation followed
by x-ray fluorescence
80
photon
yield
photon yield
150
64
48
100
32
photon yield [counts / sec]
180
4
2
0
0
2
4
16
50
0
0
0
10.5
2
1
3
pressure [bar]
1.5
4
160
140
120
100
2
80
2D
60
40
20
0
0
2.5
pressure [bar]
1
32
3
3.5
pressure [bar]
44
keV high harmonics and K-shell excitation
Inner shell excitation followed
by x-ray fluorescence
Pump laser pulse
Duration 12 fs
Intensity 7x1014 W/cm2
2.1m
Thank you