Planar buckling controlled optical conductivity of SiC monolayer from Deep-UV to visible light region: A first-principles study

TL;DR

This study uses first-principles calculations to show how planar buckling in SiC monolayers affects their electronic, optical, mechanical, and thermal properties, enabling tunable optoelectronic applications.

Contribution

It reveals the impact of controlled planar buckling on SiC monolayer's properties and demonstrates how it can be used to tune optical conductivity from deep-UV to visible light.

Findings

Buckling decreases the electronic band gap.

Optical conductivity shifts into the visible range with buckling.

Optical spectra are significantly affected by polarization and buckling.

Abstract

The electrical and optical properties of flat and planar buckled siligraphene (SiC) monolayer are examined using a first principles approach. Buckling between the Si and the C atoms in SiC structures influences and impacts the properties of the 2D nanomaterial, according to our results. The electron density of a planar SiC monolayer is calculated, as well as the effects of buckling on it. According to our findings, a siligraphene monolayer is a semiconductor nanomaterial with a direct electronic band gap that decreases as the planar buckling rises. The contributions to the density of states differ owing to changes in the system's structure. Another explanation is that planar buckling reduces the sp$^2$ overlapping, breaking the bond symmetry causing it to become a sp$^3$ bond. We show that increased planar buckling between the Si and the C atoms alters the monolayer's optical, mechanical, and thermal properties. A managed planar buckling increases the optical conductivity with a significant shift in the far visible range, as all optical spectra features are red shifted, still remaining visible. Instead of a $\sigma\text{-}\sigma$ covalent bond, the sp$^3$ hybridization produces a stronger $\sigma\text{-}\pi$ bond. Optical characteristics such as the dielectric function, the absorbance, and the optical conductivity of a SiC monolayer are investigated for both parallel and perpendicular polarization of the incoming electric field for both flat and planar buckled systems. The findings show that the optical properties are influenced for both of these two polarizations, with a significant change in the optical spectrum from the near visible to the far visible. The ability to manipulate the optical and electrical characteristics of this critical 2D material through planar buckling opens up new technological possibilities, especially for optoelectronic devices.