Magnetoplasmon spectrum for asymmetric off-plane structure of   dissipative 2D system
  The rigorous analysis of textbook result(Chiu and Quinn, 1974) gives unexpectedly the dramatic change of magnetoplasmon spectrum taking into account both the arbitrary dissipation and asymmetric off-plane structure of 2D system. For given wave vector the dissipation enhancement leads to decrease(increase) of magnetoplasmon frequency at low(high) magnetic field. At certain range of disorder the purely relaxational mode appears in magnetoplasmon spectrum. In strong magnetic fields the magnetoplasmon frequency falls to cyclotron resonance line even in presence of finite dissipation. The recent observation of 2D magnetoplasmon spectrum is consistent with our findings. 
M.V.Cheremisin
cond-mat.mes-hall