Plasmon instability in strong magnetic fields

The problem of plasmon instability of an electron-plasmon system is studied. When the plasma electron have a net drift velocity relative to the background of positive charges in the presence of a static, strong, uniform magnetic field, it is found that the plasmons may become unstable when certain value for the drift velocity is exceeded. We have studied both the general case of arbitrary Landau quantum number n and the extreme quantum limit (EQL) where the electrons are all accomodated in the lowest Landau level. In the EQL ( n =0) provided the electron cyclotron energy is greater than the thermal energy the plasmon instability occurs but it is restricted to magnetic field values greater than a critical value.