Line profiles of Ni-like collisional XUV laser amplifiers: Particle correlation effects

The effects of particle correlations on the spectral broadening due to the radiator motion (Doppler broadening) are discussed for a Ni-like XUV laser line pumped in two different regimes of collisional excitation. The transient pumping for which ionic temperature is relatively low (the plasma coupling parameters is large), and the quasi steady-state pumping (QSS) for which the ionic temperature is higher and the plasma coupling parameter of the order of 1 are considered. It is shown by using classical Molecular Dynamics simulation techniques that in both cases the effect of correlations modify the radiator-motion broadened profiles and cannot be neglected in evaluating Doppler effect. This is due to the fact that the radiator velocity changes during the radiation emission resulting in a mixing of velocities in the line profile. It is also shown that this results in a homogenization of the intrinsic line profiles.

[1]  K. Cassou,et al.  Longitudinal coherence and spectral profile of a nickel-like silver transient soft X-ray laser , 2006 .

[2]  H. J. Lee,et al.  Bremsstrahlung and line spectroscopy of warm dense aluminum plasma heated by xuv free-electron-laser radiation. , 2008, Physical review. E, Statistical, nonlinear, and soft matter physics.

[3]  I. R. Mcdonald,et al.  Theory of simple liquids , 1998 .

[4]  Troy W. Barbee,et al.  Demonstration of saturation in a Ni-like Ag x-ray laser at 14 nm , 1997 .

[5]  J. Gunn.  Atomic and molecular processes , 1977, Nature.

[6]  William L. Barr,et al.  Spectral Line Broadening by Plasmas , 1975, IEEE Transactions on Plasma Science.

[7]  Gerard Jamelot,et al.  Transient pumping of a Ni-like Ag x-ray laser with a subpicosecond pump pulse in a traveling-wave irradiation geometry , 2000 .

[8]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[9]  Stéphane Sebban,et al.  Producing ultrashort, ultraintense plasma-based soft-x-ray laser pulses by high-harmonic seeding , 2010 .

[10]  B. A. Palmer,et al.  Observation of line shifts and line profiles in an inductively coupled argon plasma , 1990 .

[11]  李幼升,et al.  Ph , 1989 .

[12]  Talin,et al.  Model for the line shapes of complex ions in hot and dense plasmas. , 1990, Physical review. A, Atomic, molecular, and optical physics.

[13]  G. J. Pert.  Optimizing the performance of nickel-like collisionally pumped x-ray lasers , 2006 .

[14]  Lebowitz,et al.  Low-frequency electric microfield distributions in plasmas. , 1985, Physical review. A, General physics.

[15]  Jorge J. Rocca,et al.  Measurement of 1-ps soft-x-ray laser pulses from an injection-seeded plasma amplifier , 2009 .

[16]  H. Griem.  Principles of Plasma Spectroscopy , 1997 .

[17]  Griem.  Line profiles of soft-x-ray laser gain coefficients. , 1986, Physical review. A, General physics.

[18]  I. R. Mcdonald,et al.  Statistical mechanics of dense ionized matter. III. Dynamical properties of the classical one-component plasma , 1975 .

[19]  R. Dicke.  The effect of collisions upon the Doppler width of spectral lines , 1953 .

[20]  Richard A. London,et al.  Absence of Dicke narrowing in x-ray laser plasmas , 1993 .

[21]  H. Griem,et al.  Stark profile calculations for Lyman series lines of one-electron ions in dense plasmas. Interim report , 1978 .

[22]  Geoffrey J. Pert,et al.  Output characteristics of amplified-stimulated-emission lasers , 1994 .

[23]  Tomas Mocek,et al.  Observation of spectral gain narrowing in a high-order harmonic seeded soft-x-ray amplifier , 2010 .

[24]  U. Fano.  Pressure Broadening as a Prototype of Relaxation , 1963 .

[25]  Underwood,et al.  Experimental and theoretical investigation of neonlike selenium x-ray laser spectral linewidths and their variation with amplification. , 1994, Physical review. A, Atomic, molecular, and optical physics.

[26]  Klein,et al.  Frequency-fluctuation model for line-shape calculations in plasma spectroscopy. , 1995, Physical review. A, Atomic, molecular, and optical physics.

[27]  F. Rosmej,et al.  Dynamic Stark broadening as the Dicke narrowing effect. , 2010, Physical review. E, Statistical, nonlinear, and soft matter physics.

[28]  J Gautier,et al.  Fourier-limited seeded soft x-ray laser pulse. , 2010, Optics letters.

[29]  J. Dubau,et al.  Temporal coherence of the Ni-like palladium x-ray laser in the transient pumping scheme , 2006 .