2021/08/17 by Soumyadeep Ghosh, Ghosh, Soumyadeep, Haranath Ghosh +1
Business, Management and Accounting · Materials Science · #FOS: Physical sciences #Intellectual Capital and Performance Analysis #Iron-based superconductors research #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.2108.07623
openalex publication_date 2021/08/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The effect of hydrostatic pressure on the electronic structures of iron\npnictide superconducting compounds LiFeAs and NaFeAs through density functional\ntheory based first principles studies are presented, using the predicted\ncrystal structures at very high pressure by Zhang et al. [1]. The orbital\nselective pressure induced modifications in the partial density of states and\nelectronic band structures reveal mixed multi-band multi-orbital nature of\nthese compounds, with energetically degenerate dxz/dyz orbitals at ambient\npressure. Due to larger hydrostatic pressures some of the electron/hole bands\ncrosses the Fermi level, leading to significant topological modifications in\nFermi surfaces known as Lifshitz transition. Interrelation between Lifshitz\ntransition and superconductivity-an important subject matter of current\nresearch are described. Based on such interconnection the current study\npredicts the superconducting-Tc in 111 compounds can not be raised at such high\npressures. Wannier functions based electronic structure investigation reveal a\nrelatively larger hybridization between the Fe-3d and As-4p orbitals at higher\npressures, as an effect of which the orbital degeneracy of dxz and dyz orbitals\nare lifted. Different hybridization contributions in the crystal-field\nsplitting are separated using the Wannier functions based formalism, by\nincorporating different bands with a particular orbital character in the\nWannier function construction. Pressure dependence of the intra/inter orbital\nhopping amplitudes between Fe-d orbitals has been discussed using low energy\ntight binding model.\n