Electron interference due to localization paths in an Aharonov-Bohm ring

Abstract

The Aharonov-Bohm effect has been investigated in mesoscopic rings fabricated from GaAs/${\mathrm{Al}}_{\mathit{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$As heterostructures constructed with a corrugated metal gate on the rings. In a certain range of the electrostatic gate voltages, two different h/e magnetoresistance oscillations have been observed near zero magnetic field, |B|${\mathit{B}}_{\mathit{c}}$. These behaviors are consistent with combining results of the magnetostatic and electrostatic Aharonov-Bohm effects of the electron wave function coherently circling around the ring. Random phases caused by the different transverse modes and their multiple localization paths reduce the interference intensity resulted from the multiple localization paths as B\ensuremath{\gtrsim}${\mathit{B}}_{\mathit{c}}$. \textcopyright{} 1996 The American Physical Society.