Observation of resonant energy transfer between identical-frequency laser beams

Enhanced transmission of a low intensity laser beam is observed when crossed with an identical-frequency beam in a plasma with a flow velocity near the ion sound speed. The time history of the enhancement and the dependence on the flow velocity strongly suggest that this is due to energy transfer between the beams via a resonant ion wave with zero frequency in the laboratory frame. The maximum energy transfer has been observed when the beams cross in a region with Mach 1 flow. The addition of frequency modulation on the crossing beams is seen to reduce the energy transfer by a factor of 2. Implications for indirect-drive fusion schemes are discussed.

[1]  R. Short,et al.  Brillouin scattering of multiline laser light in a flowing plasma corona , 1983 .

[2]  R. Kirkwood,et al.  Resonant stimulated Brillouin interaction of opposed laser beams in a drifting plasma , 1998 .

[3]  R. A. Cairns,et al.  Enhanced reflection of laser light from an expanding plasma , 1976 .

[4]  J. Wallace,et al.  An analytical and numerical investigation of ion acoustic waves in a two‐ion plasma , 1994 .

[5]  R. Kirkwood,et al.  Thomson scattering from two-species laser-produced plasmas (invited) , 1997 .

[6]  R. Kirkwood,et al.  Observation of multiple mechanisms for stimulating ion waves in ignition scale plasmas. Revision 1 , 1997 .

[7]  Villeneuve,et al.  Suppression of stimulated Raman scattering by the seeding of stimulated Brillouin scattering in a laser-produced plasma. , 1987, Physical review letters.

[8]  J. Moody,et al.  Measurements of high intensity laser beam transmission through a large scalelength plasma , 1997 .

[9]  B. Cohen,et al.  Nonlinear Mixing of Electromagnetic Waves in Plasmas , 1989, Science.

[10]  Scott C. Wilks,et al.  Energy transfer between crossing laser beams , 1996 .

[11]  Clayton,et al.  Relativistic plasma-wave excitation by collinear optical mixing. , 1985, Physical review letters.

[12]  A. Langdon,et al.  Resonantly excited nonlinear ion waves , 1997 .

[13]  J. Moody,et al.  Observation of Energy Transfer between Identical-Frequency Laser Beams in a Flowing Plasma , 1998 .

[14]  T. Tajima,et al.  Laser Electron Accelerator , 1979 .

[15]  A. C. Gaeris,et al.  The frequency and damping of ion acoustic waves in hydrocarbon (CH) and two‐ion‐species plasmas , 1995 .

[16]  Peter A. Amendt,et al.  Design and modeling of ignition targets for the National Ignition Facility , 1995 .

[17]  J. Moody,et al.  Evidence of plasma fluctuations and their effect on the growth of stimulated Brillouin and stimulated Raman scattering in laser plasmas , 1998 .

[18]  N. Kroll,et al.  Optical Mixing as a Plasma Density Probe , 1964 .

[19]  A. Schmitt,et al.  Time-dependent filamentation and stimulated Brillouin forward scattering in inertial confinement fusion plasmas , 1998 .

[20]  Dyson,et al.  Ultrahigh-gradient acceleration of injected eletrons by laser-excited relativistic electron plasma waves. , 1993, Physical review letters.

[21]  C. McKinstrie,et al.  POWER EXCHANGE BETWEEN CROSSED LASER BEAMS AND THE ASSOCIATED FREQUENCY CASCADE , 1997 .

[22]  S. Ghosal,et al.  Nonlinear theory of power transfer between multiple crossed laser beams in a flowing plasma , 1998 .

[23]  B. Stansfield,et al.  ENHANCED SCATTERING OF LASER LIGHT BY OPTICAL MIXING IN A PLASMA. , 1971 .

[24]  C. McKinstrie,et al.  Transient Filamentation of a Laser Beam in a Thermal Force Dominated Plasma , 1996 .

[25]  C. Capjack,et al.  Interaction of crossed laser beams with plasmas , 1996 .

[26]  Bedros Afeyan,et al.  Kinetic Theory of Electron-Plasma and Ion-Acoustic Waves in Nonuniformly Heated Laser Plasmas , 1998 .

[27]  Moody,et al.  Observation of energy transfer between frequency-mismatched laser beams in a large-scale plasma. , 1996, Physical review letters.

[28]  H T Powell,et al.  Designing fully continuous phase screens for tailoring focal-plane irradiance profiles. , 1996, Optics letters.