Oscillations of the static meson fields at finite baryon density
  The spatial dependence of static meson correlation functions at finite baryon density is studied in the Nambu -- Jona - Lasinio model. In contrast to the finite temperature case, we find that the correlation functions at finite density are not screened but exhibit long-range oscillations. The observed phenomenon is analogous to the Friedel oscillations in a degenerate electron gas. 
W. Florkowski and B. Friman