Electron-doped phosphorene: A potential monolayer superconductor

Abstract

-We predict by first-principles calculations that the electron-doped phosphorene is a potential BCS-like superconductor. The stretching modes at the Brillouin-zone center are remarkably softened by the electron-doping, which results in the strong electron-phonon coupling. The superconductivity can be introduced by a doped electron density (n2D) above 1.3 × 10 14 cm −2 , and may exist over the liquid helium temperature when n2D > 2.6 × 10 14 cm −2 . The superconductivity can be significantly tuned and enhanced by applying tensile strain. The maximum critical temperature of electron doped phosphorene is predicted to be higher than 10 K. The superconductivity of phosphorene will significantly broaden the applications of this novel material.The two-dimensional (2D) monolayer superconductor bears consequences for both applications and fundamental science. It can be used as the component of nanoscale superconducting devices, such as nano superconducting quantum interference devices and nano superconducting transistors [1][2][3][4][5], with the goal of achieving single-spin sensitivity for measuring and controlling. Moreover, the high-T c superconductors with the quasi-2D layered structures, such as MgB 2 [6], cuprate superconductors [7,8], and ironbased superconductors [9], can be seen as the assembly of multiple monolayers. Geim et al. [10] proposed to construct the high-T c -superconductor-like Van der Waals heterostructures using the monolayer superconductors, which may be helpful for the exploration of new high-T c superconductors. A graphene-like monolayer superconductor seems to be the natural choice of such applications. It is suggested that the carrier-doped graphene [11][12][13] and graphane [14] may exhibit superconductivity with notable T c . However, the experimental evidences are still lacking. Using the liquid-gate method, one can introduce the superconductivity into the few-layer semiconductor MoS 2 [15], which may be driven by the electron-phonon coupling (a) E-mail: wjlu@issp.ac.cn (b) E-mail: ypsun@issp.ac.cn [16]. But the thickness of such material is still far from one layer. More monolayer superconductor candidates still need to be found.Here we show a potential monolayer superconductor: electron-doped phosphorene. Based on the density functional theory (DFT) calculations, we found the electrondoping can make the stretching modes at zone center significantly softened, leading to a strong electron-phonon coupling. The superconductivity starts showing up when the carrier density (n 2D ) is 1.3 × 10 14 cm −2 . When n 2D > 2.6 × 10 14 cm −2 , the T c exceeds the liquid helium temperature. Moreover, the application of tensile strain can significantly tune and enhance the superconductivity. The maximum T c is predicted to be higher than 10 K. Our prediction can be readily verified by the liquid-gate method [15,[17][18][19], or the adsorption of the alkali/alkalineearth metal atoms. Figure 1 shows the structures of bulk black phosphorus (black-P) and monolayer black-P (which is called phosphoren...

Toward a realistic description of multilayer black phosphorus: FromGWapproximation to large-scale tight-binding simulations

“…Apart from the practical aspect, there is a growing fundamental interest in BP ranging from attempts to provide insight into the origin of its band properties [8] to more exotic and speculative aspects including superconductivity [9] and topologically nontrivial phases [10].…”

Recent advances in synthesis, properties, and applications of phosphorene

“…For example, the application of uniaxial stress can break the symmetry and enhance in-plane anisotropy. 72 Other effects include electron-phonon coupling enhancement, 73 superconductivity, 74 semiconductor to metal transition, 75 band gap modification, 15 and direct-indirect band gap transition 12 ( Fig. 5).…”

Prediction of above 20 K superconductivity of blue phosphorus bilayer with metal intercalations

“…To the best of our knowledge, superconductivity of Blue-P has not been investigated, it may be different from the Black-P case considering their different crystalline and electronic structures [8,11]. In this paper, we will study the lattice dynamics and superconductivity of bilayer Blue-P intercalating with Li, Na and Mg, using the first-principles density functional theory (DFT) and density function perturbation theory (DFPT).…”