Electronic Structures of Newly Discovered Quasi-One-Dimensional Superconductors A2Mo3As3 (A=K,Rb,Cs)

Electronic structures of the newly discovered quasi-one-dimensional superconductors A2Mo3As3 (A=K, Rb and Cs) are studied through first-principles calculations. We find that the bond lengths within the [Mo6As6]4− chains are robust against the replacement of alkali cations, leading to quite similar electronic structures among the three members. Three bands cross the Fermi level and form two quasi-one-dimensional Fermi surfaces as well as one three dimensional component. The obtained density of states near the Fermi level show great Mo-4d orbitals character, in particular the dz2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {d}_{z^2} $$\end{document}, dxy and dx2−y2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {d}_{x^2-{y}^2} $$\end{document} orbitals. Our calculations show that A2Mo3As3 share great similarity in electron properties with extensively studied A2Cr3As3, indicating that A2Mo3As3 are probably another family of unconventional quasi-one-dimensional superconductors.