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