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arXiv · 1408.3509

Topological tuning in three-dimensional Dirac semimetals

Awadhesh Narayan·Domenico Di Sante·Silvia Picozzi·Stefano Sanvito
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Abstract

We study with first-principles methods the interplay between bulk and surface Dirac fermions in three dimensional Dirac semimetals. By combining density functional theory with the coherent potential approximation, we reveal a topological phase transition in Na$_3$Bi$_{1-x}$Sb$_{x}$ and Cd$_3$[As$_{1-x}$P$_x$]$_2$ alloys, where the material goes from a Dirac semimetal to a trivial insulator upon changing Sb or P concentrations. Tuning the composition allows us to engineer the position of the bulk Dirac points in reciprocal space. Interestingly, the phase transition coincides with the reversal of the band ordering between the conduction and valence bands.

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Awadhesh Narayan, Domenico Di Sante, Silvia Picozzi, Stefano Sanvito. 2014-12-17. Topological tuning in three-dimensional Dirac semimetals. https://doi.org/10.1103/physrevlett.113.256403

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