Electric bias control on impurity effects in bigraphene

TL;DR

This paper investigates how electric bias influences impurity-induced localized states in bigraphene, revealing controllable metal-insulator transitions that could be useful for nanoelectronics.

Contribution

It demonstrates the conditions for impurity level collectivization and spectrum restructuring in bigraphene under electric bias, a novel insight into impurity effects in this material.

Findings

Localized impurity levels form within the band gap under electric field.

Electric bias can induce metal-insulator phase transitions in bigraphene.

These effects are controllable and promising for nanoelectronic applications.

Abstract

Formation of localized impurity levels within the band gap in bigraphene under applied electric field is considered and the conditions for their collectivization at finite impurity concentration are established. It is shown that a qualitative restructuring of quasiparticle spectrum within the initial band gap and then specific metal-insulator phase transitions are possible for such disordered system and can be effectively controlled by variation of the electric field bias at given impurity perturbation potential and concentration. Since these effects can be expected at low impurity concentrations but at not too low temperatures, they can be promising for practical applications in nanoelectronics devices.