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arXiv · 1502.04103

Surface state reconstruction in ion-damaged SmB_6

N. Wakeham·Y. Q. Wang·Z. Fisk·F. Ronning·J. D. Thompson
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Abstract

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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N. Wakeham, Y. Q. Wang, Z. Fisk, F. Ronning, J. D. Thompson. 2015-02-13. Surface state reconstruction in ion-damaged SmB_6. https://doi.org/10.1103/physrevb.91.085107

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