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Surface state reconstruction in ion-damaged SmB_6

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 Added by Nicholas Wakeham
 Publication date 2015
  fields Physics
and research's language is English
 Authors N. Wakeham




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We have used ion-irradiation to damage the (001) surfaces of SmB_6 single crystals to varying depths, and have measured the resistivity as a function of temperature for each depth of damage. We observe a reduction in the residual resistivity with increasing depth of damage. Our data are consistent with a model in which the surface state is not destroyed by the ion-irradiation, but instead the damaged layer is poorly conducting and the initial surface state is reconstructed below the damage. This behavior is consistent with a surface state that is topologically protected.



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