Monolayer SiP nanosheets for near and mid-infrared optoelectronic device applications - A DFT approach

The invention of geometrically stable low-dimensional semiconductors along with excellent electronic properties is significant to future optoelectronic devices. Using Ab initio technique, we predict the monolayer silicon phosphide nanosheet (SiP-NS) as a good candidate for near and far-infrared optoelectronic devices due to its excellent dynamical stabilities, more chance for experimental exfoliation, fine-tune the electronic properties with the substitution of proper dopant atoms and prominent anisotropy. The structural and dynamical stability of pristine, Al and B substituted SiP-NS are verified by the cohesive energy and phonon-band-structure. The electronic properties of SiP-NS are demonstrated with the support of the density of states spectrum and energy band structure. The direct energy gap value of pristine SiP-NS is found to be 1.34 eV. The main objective of the proposed research article is to fine tune the electronic characteristics of SiP-NS by the substitution of Al and B atom. Pristine Al and B substituted SiP-NS, with dynamical stability and direct band gap, is a promising material for two dimensional near and mid-infrared optoelectronic devices.