Superconductivity in Li-intercalated bilayer arsenene and hole-doped monolayer arsenene: a first-principles prediction

Abstract

Using first-principles calculations, we find Li-intercalated bilayer arsenene with AB stacking is dynamically stable, which is different from pristine bilayer with AA stacking. Electron-phonon coupling of the stable Li-intercalated bilayer arsenene are dominated by the low frequency vibrational modes (E″(1), [Formula: see text](1), E'(1) and acoustic modes) and lead to an superconductivity with T = 8.68 K with isotropical Eliashberg function. Small biaxial tensile strain (2%) can improve T to 11.22 K due to the increase of DOS and phonon softening. By considering the fully anisotropic Migdal-Eliashberg theory, T are found to be enhanced by 50% and exhibits a single anisotropic gap nature. In addition, considering its nearly flat top valence band which is favorable for high temperature superconductivity, we also explore the superconducting properties of hole-doped monolayer arsenene under different strains. the unstrained monolayer arsenene superconducts at T = 0.22 K with 0.1 hole/cell doping. By applying 3% biaxial strain, T can be lifted up strikingly to 6.69 K due to a strong Fermi nesting of the nearly flat band. Then T decreases slowly with strain. Our findings provide another insight to realize 2D superconductivity and suggest that the strain is crucial to further enhance the transition temperature.

Prediction of superconductivity in sandwich XB4 (X = Li, Be, Zn and Ga) films

“…Since the enhancement of the EPC λ is related to the electron states generated by doping metal atoms near the Fermi level, it had been anticipated that metal atoms (Li, Ca) intercalated in these bilayer systems would give rise to phonon-mediated superconductivity. 11–17 Experiments and theoretical calculations have confirmed the T c at 2 K in Ca-intercalated bilayer graphene (C 6 CaC 6 ). 11 Recent studies examined how the presence of hydrogen adatoms affects the superconducting properties of monolayer MgB 2 , and they found that the electronic density of states at the Fermi level and the electron–phonon coupling, both increase dramatically which in turn enhanced the T c up to 67 K. 18,19…”

Review on 2D Arsenene and Antimonene: Emerging Materials for Energy, Electronic and Biological Applications

“…The intercalated Li atoms change the interlayer interaction in arsenene from the weak vdW type to the Coulomb type. [86] Zhao et al have studied monolayer As x Sb y alloys, where x and y denote the atomic ratio of As and Sb elements and x + y = 16. The results show that the AsAs and AsSb bonds stabilize the alloy structure while the SbSb bond deteriorates the stability.…”

“…The intercalated Li atoms change the interlayer interaction in arsenene from the weak vdW type to the Coulomb type. [ 86 ] Zhao et al. have studied monolayer As x Sb y alloys, where x and y denote the atomic ratio of As and Sb elements and x + y = 16.…”

Topological phase transition and tunable electronic properties of hydrogenated bismuthene: from single-layer to double-layer

“…Another effective way to tune the electronic properties of van der Waals DL is via metal atom intercalation. This has been comprehensively investigated in bilayer graphene [74] and bilayer arsenene [75], and tunable electronic properties and novel superconducting properties are demonstrated in these bilayer systems. Here Na, Mg, and K are acted as the interca lation atoms.…”