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

Abstract

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 2×10 15 m -2 and 1×10 16 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 \(\hat{\varepsilon }=(1+\varepsilon _{\rm GaAs})/2\) where e 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.