PLASMON INSTABILITY IN STRONG MAGNETIC-FIELDS

The problem of plasmon instability of an electron-plasmon system is st udied. 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 uns table when certain value for the drift velocity is exceeded. We have s tudied both the general case of arbitrary Landau quantum number n and the extreme quantum limit (EQL) where the electrons are all accomodate d in the lowest Landau level. In the EQL (n = 0) provided the electron cyclotron energy is greater than the thermal energy the plasmon insta bility occurs but it is restricted to magnetic field values greater th an a critical value.