Applied Surface Science, Vol.445, 161-166, 2018
First-principles studies on the superconductivity of aluminene
Group III mono-elemental two-dimensional (2D) materials have been an active area of research since the experimental demonstration of monolayer boron. Using first-principles calculations, we predict a new type of buckled monolayer aluminum (aluminene) which exhibits metallic characteristics. From the phonon dispersion and cohesive energy calculations, the free-standing aluminene is structurally stable. The stability of the aluminene is maintained under tensile strain up to 7%. In contrast, the stability of the structure is not preserved in the presence of compressive strain. We also carried out a systematic analysis on the electron-phonon coupling in the aluminene structure and found that aluminene in its pristine form can superconduct with superconductivity critical temperature, T-c of 6.5 K. The T-c is further enhanced to 11.9 K with the presence of 7% bi-axial tensile strain. Our calculations show that the higher T-c is because of stronger electron-phonon coupling resulted from the increase of density of states at Fermi level with tensile strain. (C) 2018 Elsevier B.V. All rights reserved.