Atomic Structure of the GaAs 001 - 2 3 4 Surface Resolved Using Scanning Tunneling Microscopy and First-Principles Theory
نویسندگان
چکیده
The atomic arrangement of the technologically important As-rich GaAs 001 2 3 4 reconstructed surface is determined using bias-dependent scanning tunneling microscopy (STM) and first-principles electronic structure calculations. The STM images reveal the relative position and depth of the atomicscale features within the trenches between the top-layer As dimers, which are in agreement with the b2 2 3 4 structural model. The bias-dependent simulated STM images reveal that a retraction of the topmost dangling bond orbitals is the novel electronic mechanism that enables the STM tip to image the trench structure.
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