X-ray Raman compression via two-stream instability in dense plasmas
  A Raman compression scheme suitable for x-rays, where the Langmuir wave is created by an intense beam rather than the pondermotive potential between the seed and pump pulses, is proposed.   The required intensity of the seed and pump pulses enabling the compression could be mitigated by more than a factor of 100, compared to conventionally available other Raman compression schemes. The relevant wavelength of x-rays ranges from 1 to 10 nm. 
S. Son and Sung Joon Moon
physics.plasm-ph physics.flu-dyn quant-ph