Electric bias control of impurity effects in bilayer graphene

Formation of localized impurity levels within the band gap in bigraphene under applied electric field and the conditions for their collectivization at finite impurity concentrations are considered. It is shown that a qualitative restructuring of the quasiparticle spectrum within the initial band gap and subsequent metal-insulator phase transitions are possible for such disordered systems, being effectively controlled by variation of the electric field bias. Since these effects can be expected at low enough impurity concentrations and accessible applied voltages, they can be promising for practical applications in nanoelectronics devices.