Dynamical stability, electronic structure and optical absorption of strained penta-graphene monolayer: an ab-initio study

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2024-11, Vol.130 (11), Article 840
• Main Authors: Minaie, B., Ketabi, Seyed Ahmad, De Sousa, J. M.
• Format: Article
• Language: English
• Subjects: Absorption spectra; Absorptivity; Approximation; Characterization and Evaluation of Materials; Compressive properties; Condensed Matter Physics; Density functional theory; Electronic structure; Energy gap; Excitation spectra; Graphene; Machines; Manufacturing; Monolayers; Nanotechnology; Optical and Electronic Materials; Optical properties; Physics; Physics and Astronomy; Processes; Red shift; Stability; Surfaces and Interfaces; Tensile strain; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-024-08021-5

In this work, based on density functional theory (DFT) calculations and using more accurate many-body perturbation GW theory, we discuss how uniform biaxial strain affects the electronic structure, dynamical stability and optical absorption of the low-buckled penta-graphene (PG) monolayer. We found that under compressive strain, the PG structure becomes dynamically unstable, while under the tensile strain, it maintains the dynamical stability. Our findings reveal that PG behaves as a semiconductor with an indirect band gap of 2.27 eV at the DFT-GGA level which increases to a quasi-direct band gap of 4.62 eV in G 0 W 0 approximation. However, under tensile strain, the band gap magnitude is reduced monotonically in G 0 W 0 approximation. Furthermore, we employed the G 0 W 0 -RPA and G 0 W 0 -BSE approximations to compute the optical absorption spectra of the monolayer PG under compressive/tensile strain. Our results demonstrate that at the G 0 W 0 -BSE level, when the excitonic effects is considered, both in the strain-free and strained PG monolayer, all absorption spectra shift to lower energies (redshift). However, under tensile strain from 0 to 10%, there is an upward trend in the maximum absorption coefficient. Our results highlight the tunability of the electronic band gap and optical properties of monolayer PG under biaxial strain.