Classical Edge Magnetoplasmon in a GaAs/AlGaAs Two-Dimensional Electron System

抄録

We have studied the edge magnetoplasmon (EMP) in a GaAs/AlGaAs two-dimensional electron gas (2DEG) system under conditions where the quantum Hall effect (QHE) is not observed; we call this a classical EMP. The classical EMP's are excited in a 2DEG disk by radio frequency electric field excitation (≤ 1, GHz) in a high magnetic field B (≤ 5, T) with the 2DEG sheet carrier density n_s between 2× 10¹⁵, m^-2 and 1× 10¹⁶, m^-2. The resonant frequency is found to be almost proportional to n_s and inversely proportional to B, which agrees quantitatively with the theory proposed by Volkov and Mikhailov, Sov. Phys.-JETP 67 (1988) 1639 by assuming the effective dielectric constant ε\circ =(1+ε _GaAs)/2 where ε _GaAs is appropriate to the GaAs. A comparison of the experimental results with the calculations revealed that the electron mobility plays an important role in the definition of the EMP frequency.