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arXiv · 2105.14916

Phase stability in SmB$_6$

M. Victoria Ale Crivillero·Sahana Rößler·H. Borrmann·H. Dawczak-Dȩbicki·Priscila F. S. Rosa·Z. Fisk·S. Wirth
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Abstract

We investigate flux-grown Sm-deficient Sm$_x$B$_6$ ($x < 1$) by global and local tools, including X-ray diffraction (XRD), electronic transport, and scanning tunneling microscopy (STM) and spectroscopy (STS). All these tools indicate a remarkable persistence of the SmB$_6$ local structure in the flux-grown samples even for nominal Sm concentrations as low as $x=0.75$. As a consequence, the overall electronic properties of Sm$_x$B$_6$, and particularly the surface conductance at low temperature, is only affected locally by the Sm-deficiency.

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M. Victoria Ale Crivillero, Sahana Rößler, H. Borrmann, H. Dawczak-Dȩbicki, Priscila F. S. Rosa, Z. Fisk, S. Wirth. 2021-05-31. Phase stability in SmB$_6$. https://doi.org/10.1103/physrevmaterials.5.044204

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