Tuning of the Optical Properties of Monolayer Blue Phosphorene

Blue and black phosphorus are the most stable allotropes of phosphorus family. As a new potential semiconductor material, blue phosphorene shows the advantage of its wide indirect bandgap. We investigate fundamental optical properties and tunability of the bandgap of monolayer blue phosphorene based on density functional theory. Our comparative analysis reveals the bandgap adjustability of blue P along the polarization direction and that the plasmons resonance mode of blue phosphorene in different polarization directions. Besides, we report a unique 2D rectangular semiconductor-metal hybrid nanostructures, the monolayer rectangle blue phosphorene inserted into the Au nanowires. Owing to surface plasmon polaritons (SPPs), the absorption spectra of blue phosphorene is broadened and shifted to the infrared region, in which strong characteristic peaks appear and the existence of the coupling of single electron motion and coherent vibration is proved. The results provide the novle principle for optical modulation of blue phosphorene and possible applications in nanoscale plasma devices.