Influence of surface states on tunneling spectra of n-type GaAs(110) surfaces
نویسندگان
چکیده
We show that surface states within the conduction band of n-type GaAs 110 surfaces play an important role in reducing the tunneling current out of an accumulation layer that forms due to an applied potential from a nearby probe tip. Numerical computation of the tunneling current combined with an electrostatic potential computation of the tip-induced band bending TIBB reveals that occupation of the surface states limits the TIBB, thus leading to the limitation of the accumulation. As a result, the tunneling current out of the accumulation layer is strongly suppressed, which is in quantitative agreement with the experiment.
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