Full-mode analysis of the plasmon oscillations of 2D electron gas subjected to electric field

Plasmon dispersion law including wave vector dependencies of the oscillation frequency, ω'(q), and the damping ω''(q) of 2D electron gas subjected to the steady-state electric field were analyzed in the frameworks of general kinetic theory of collisionless plasma. Two particular cases of ungated and gated 2D electron gas were considered. We found that the spectra of 2D plasmons have the following peculiarities: multi-branched character, strong dependence of Landau damping vs dielectric surrounding of 2D gas, the strong non-reciprocal dispersion with respect to the direction of electron drift, existence of an extended instability range of wavevectors where plasmons propagating along the electron drift have essential increment of oscillations, ω'' > 0. Also, the effect of the mode interaction under applied field was identified.