Modulation of the Electronic Properties of Ultrathin Black Phosphorus by Strain and Electrical Field

Abstract

The structural and electronic properties of the bulk and ultrathin black phosphorus and the effects of in-plane strain and out-of-plane electrical field on the electronic structure of phosphorene are investigated using first-principles methods. The computed results show that the bulk and few-layer black phosphorus from monolayer to six-layer demonstrates inherent direct bandgap features ranging from 0.5 to 1.6 eV. Interestingly, the band structures of the bulk and few-layer black phosphorus from X point via A point to Y point present degenerate distribution, which shows totally different partial charge dispersions. Moreover, strong anisotropy in regard to carrier effective mass has been observed along different directions. The response of phosphorene to in-plane strain is diverse. The bandgap monotonically decreases with increasing compressive strain, and semiconductor-tometal transition occurs for phosphorene when the biaxial compressive reaches −9%. Tensile strain first enlarges the gap until the strain reaches around 4%, after which the bandgap exhibits a descending relationship with tensile strain. The bandgaps of the pristine and deformed phosphorene can also be continuously modulated by the electrical field and finally close up at about 15 V/ nm. Besides, the electron and hole effective mass along different directions exhibits different responses to the combined impact of strain and electrical field.

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

“…8(f). Our results obtained using the TB model are thus consistent with previous DFT calculations for a few-layer BP and phosphorene nanoribbons [10,23,[55][56][57].…”

Nanotubes based on monolayer blue phosphorus

“…Another similarity is the sensitive dependence of the band gap on axial strain, which is useful in electronic applications [33]. For strain between −8% (compression) and +8% (tensile) this dependence is shown in Fig.…”

Probing the anisotropic behaviors of black phosphorus by transmission electron microscopy, angular-dependent Raman spectra, and electronic transport measurements

“…8 The thickness-dependent Raman intensity can be explained by the changes in Raman tensor elements in R influenced by the variation of electron-phonon dispersion 38 that typically arises from the changes in atomic structure. 7,19,39,40 Hence, we believe that the stretching or shrinking of the lattice parameter significantly influences the dielectric constant and electron-phonon dispersion, which then modulate the a and c Raman tensor element values.…”