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The loss of anisotropy in MgB2 with Sc substitution and its relationship with the critical temperature

Sabina Ruiz-Chavarria·Gustavo Tavizon·Pablo de la Mora
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Abstract

The electrical conductivity anisotropy of the sigma-bands is calculated for the (Mg,Sc)B2 system using a virtual crystal model. Our results reveal that anisotropy drops with relatively little scandium content (< 30%); this behaviour coincides with the lowering of Tc and the reduction of the Kohn anomaly. This anisotropy loss is also found in the Al and C doped systems. In this work it is argued that the anisotropy, or 2D character, of the sigma-bands is an important parameter for the understanding of the high Tc found in MgB2.

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Sabina Ruiz-Chavarria, Gustavo Tavizon, Pablo de la Mora. 2005-07-19. The loss of anisotropy in MgB2 with Sc substitution and its relationship with the critical temperature. https://doi.org/10.1088/0953-8984%2F18%2F4%2F024

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