Topological Transition in Pb1-xSnxSe using Meta-GGA Exchange-Correlation Functional. Acta Physica Polonica A 136, 667 (2019), ERRATUM

Topological transition in Pb1-xSnxSe using Meta-GGA

We calculate the mirror Chern number (MCN) and the band gap for the alloy Pb1-xSnxSe as a function of the concentration x by using virtual crystalline approximation. We use the electronic structure from the relativistic density functional theory calculations in the Generalized-Gradient- Approximation (GGA) and meta-GGA approximation. Using the modified Becke-Johnson meta- GGA functional, our results are comparable with the available experimental data for the MCN as well as for the band gap. We advise to use modified Becke-Johnson approximation with the parameter c=1.10 to describe the transition from trivial to topological phase for this class of compounds.

Multiple band crossings and Fermi surface topology: Role of double nonsymmorphic symmetries in MnP-type crystal structures

We use relativistic ab-initio methods combined with model Hamiltonian approaches to analyze the normal-phase electronic and structural properties of the recently discovered WP superconductor. Remarkably, the outcomes of such study can be employed to set fundamental connections among WP and the CrAs and MnP superconductors belonging to the same space group. One of the key features of the resulting electronic structure is represented by the occurrence of multiple band crossings along specific high symmetry lines of the Brilloiun zone. In particular, we demonstrate that the eight-fold band degeneracy obtained along the SR path at (kx,ky)=(Pi,Pi) is due to inversion-time reversal invariance and…