Local 2D-2D tunneling in high mobility electron systems
ORAL
Abstract
Many scanning probe techniques have been utilized in recent years to measure local properties of high mobility two-dimensional (2D) electron systems in GaAs. However, most techniques lack the ability to tunnel into the buried 2D system and measure local spectroscopic information. We report scanning gate measurements on a bilayer GaAs/AlGaAs heterostructure that allows for a local modulation of tunneling between two 2D electron layers. We call this technique Virtual Scanning Tunneling Microscopy (VSTM) [1,2] as the influence of the scanning gate is analogous to an STM tip, except at a GaAs/AlGaAs interface instead of a surface. We will discuss the spectroscopic capabilities of the technique, and show preliminary results of measurements on a high mobility 2D electron system.\newline [1] A. Sciambi, M. Pelliccione \textit{et al.}, Appl. Phys. Lett. \textbf{97}, 132103 (2010).\newline [2] A. Sciambi, M. Pelliccione \textit{et al.}, Phys. Rev. B \textbf{84}, 085301 (2011).
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