Phase transition and electronic tuning in gamma-graphynenanoribbons through uniaxial strain and electric field

Abstract

Gamma-graphyne sheet is a semiconductor with a bandgap of about 0.5 eV. For electronic applications, we need a tunable energy gap. For this purpose, we introduce a tight-binding based method which enables us to study the effects of oriented strains and also electric fields on electronic properties of nanoribbons of monolayer gamma-graphyne. Our results shows that the system has a controllable bandgap in the range of 0–2.9 eV in response to a transverse electric field and strain. Applying a transverse electric field and strain causes a semiconductor-metal phase transition. One can control the bandgap and electronic properties of the system with the help of the above parameters. Our findings indicate that the γ-graphynenanoribbons are promising candidate for applications in high efficiency nanoelectronic devices. • We investigate the electronic properties of armchair and zigzag γ-graphynenanoribbons. • We introduce a tight-binding based method which enables us to study the effects of oriented strains and also electric fields. • Our results shows that the system has a controllable bandgap in the range of 0–2.9 eV. • Due to the giant Stark effect, the band gap of the system is closed at a critical field. • A semiconductor-metal phase transition occurs in the system.