Electron-phonon properties and superconductivity of doped antimonene

TL;DR

This study computationally investigates electron-phonon interactions and potential superconductivity in doped antimonene, highlighting how electric fields influence stability, electronic structure, and superconducting properties, with electron-doped antimonene showing promising superconducting behavior.

Contribution

It provides new insights into how electric fields affect electron-phonon coupling and superconductivity in doped antimonene, especially under different doping conditions.

Findings

Electron-doped antimonene remains stable and can exhibit strong electron-phonon coupling.

Superconductivity with a critical temperature of around 16 K is predicted in electron-doped antimonene.

Electric fields significantly modify electronic structure and superconducting properties, especially in hole-doped antimonene.

Abstract

Antimonene is a recently discovered two-dimensional semiconductor with exceptional environmental stability, high carrier mobility, and strong spin-orbit interactions. In combination with electric field, the latter provides an additional degree of control over the materials' properties because of induced spin splitting. Here, we report on a computational study of electron-phonon coupling and superconductivity in $n$- and $p$-doped antimonene, where we pay a special attention on the effect of the perpendicular electric field. The range of accessible hole concentrations is significantly limited by the dynamical instability, associated with strong Fermi-surface nesting. At the same time, we find that in case of electron-doping antimonene remains stable and can be turned into a state with strong electron-phonon coupling, with the mass enhancement factor $\lambda$ of up to 2.3 at realistic charge carrier concentrations. In this regime, antimonene is expected to be a superconductor with the critical temperature of $\sim$16 K. Application of bias voltage leads to a considerable modification of the electronic structure, affecting the electron-phonon coupling in antimonene. While these effects are less obvious in case of electron-doping, field-effect in hole-doped antimonene results in a considerable variation of the critical temperature depending on bias voltage.