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STM images of sub-surface Mn atoms in GaAs: evidence of hybridization of surface and impurity states

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 Added by Jancu Jean-Marc
 Publication date 2008
  fields Physics
and research's language is English




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We prove that scanning tunneling microscopy (STM) images of sub-surface Mn atoms in GaAs are formed by hybridization of the impurity state with intrinsic surface states. They cannot be interpreted in terms of bulk-impurity wavefunction imaging. High atomic resolution images obtained using a low-temperature apparatus are compared with advanced, parameter-free tight-binding simulations accounting for both the buckled (110) surface and vacuum electronic properties.



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