Negative energy waves and quantum relativistic Buneman instabilities
  The quantum relativistic Buneman instability is investigated theoretically using a collective Klein-Gordon model for the electrons and a cold fluid model for the ions. The growth rate and unstable wave spectrum is investigated in different parameter regimes corresponding to various degrees of relativistic and quantum effects. The results may be important for streaming instabilities involving ion dynamics in very dense plasmas. 
F. Haas, B. Eliasson and P. K. Shukla
physics.plasm-ph