Nanoscale femtosecond imaging of transient hot solid density plasmas with elemental and charge state sensitivity using resonant coherent diffraction

Here, we propose to exploit the low energy bandwidth, small wavelength, and penetration power of ultrashort pulses from XFELs for resonant Small Angle Scattering (SAXS) on plasma structures in laser excited plasmas. Small angle scattering allows to detect nanoscale density fluctuations in forward scattering direction. Typically, the SAXS signal from laser excited plasmas is expected to be dominated by the free electron distribution. We propose that the ionic scattering signal becomes visible when the X-ray energy is in resonance with an electron transition between two bound states (resonant coherent X-ray diffraction). In this case, the scattering cross-section dramatically increases so that the signal of X-ray scattering from ions silhouettes against the free electron scattering background which allows to measure the opacity and derived quantities with high spatial and temporal resolution, being fundamentally limited only by the X-ray wavelength and timing. Deriving quantities such as ion spatial distribution, charge state distribution, and plasma temperature with such high spatial and temporal resolution will make a vast number of processes in shortpulse laser-solid interaction accessible for direct experimental observation, e.g., hole-boring and shock propagation, filamentation and instability dynamics, electron transport, heating, and ultrafast ionization dynamics.

[1]  J. Als-Nielsen,et al.  Elements of Modern X-ray Physics: Als-Nielsen/Elements , 2011 .

[2]  Ian McNulty,et al.  Nanoscale imaging of buried structures with elemental specificity using resonant x-ray diffraction microscopy. , 2008, Physical review letters.

[3]  Michael Bussmann,et al.  Ion heating dynamics in solid buried layer targets irradiated by ultra-short intense laser pulses , 2013 .

[4]  K Mima,et al.  Three-dimensional particle-in-cell simulations of energetic electron generation and transport with relativistic laser pulses in overdense plasmas. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[5]  Michael Bussmann,et al.  Using X-ray free-electron lasers for probing of complex interaction dynamics of ultra-intense lasers with solid matter , 2013, 1306.0420.

[6]  Yasuhiko Sentoku,et al.  Hot electron generation forming a steep interface in superintense laser-matter interaction , 2009 .

[7]  J. Linnett,et al.  Quantum mechanics , 1975, Nature.

[8]  Scott C. Wilks,et al.  X-ray spectroscopy of buried layer foils irradiated at laser intensities in excess of 1020 W/cm2 , 2009 .

[9]  Yasuhiko Sentoku,et al.  Numerical methods for particle simulations at extreme densities and temperatures: Weighted particles, relativistic collisions and reduced currents , 2008, J. Comput. Phys..

[10]  T. Kluge,et al.  Two surface plasmon decay of plasma oscillations , 2015, 1501.07311.

[11]  R. Stephens,et al.  Effect of target material on fast-electron transport and resistive collimation. , 2013, Physical review letters.

[12]  J. Lüning,et al.  Nanoscale imaging with resonant coherent X rays: extension of multiple-wavelength anomalous diffraction to nonperiodic structures. , 2008, Physical review letters.

[13]  K. Tanaka,et al.  Stopping and transport of fast electrons in superdense matter , 2013 .

[14]  Epstein,et al.  Electron-temperature measurement in laser-produced plasmas by the ratio of isoelectronic line intensities. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[15]  M. Desjarlais,et al.  Annular fast electron transport in silicon arising from low-temperature resistivity. , 2013, Physical review letters.

[16]  46 , 2015, Slow Burn.

[17]  R. More Pressure Ionization, Resonances, and the Continuity of Bound and Free States , 1985 .

[18]  Richard Lee,et al.  Extension of atomic configuration sets of the Non-LTE model in the application to the Kα diagnostics of hot dense matter , 2007 .

[19]  M. Borghesi,et al.  Generation and optimization of electron currents along the walls of a conical target for fast ignition , 2010 .

[20]  Stefan Eisebitt,et al.  Coherent imaging of biological samples with femtosecond pulses at the free-electron laser FLASH , 2010 .

[21]  Andrew G. Glen,et al.  APPL , 2001 .

[22]  Carl Eklund,et al.  National Institute for Standards and Technology , 2009, Encyclopedia of Biometrics.

[23]  C. Deutsch,et al.  Collective electromagnetic modes for beam-plasma interaction in the whole k space. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[24]  X. H. Li,et al.  Effect of resistivity gradient on laser-driven electron transport and ion acceleration , 2013 .

[25]  A. Kemp,et al.  Isochoric heating in heterogeneous solid targets with ultrashort laser pulses , 2007 .

[26]  Yasuhiko Sentoku,et al.  Collisional particle-in-cell modeling for energy transport accompanied by atomic processes in dense plasmas , 2013 .

[27]  S. Wilks,et al.  Experimental Characterization of a Strongly Coupled Solid Density Plasma Generated in a Short‐pulse Laser Target Interaction , 2005 .

[28]  J. Als-Nielsen,et al.  Elements of Modern X-ray Physics , 2001 .