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We investigate the electronic structures of some defective boron nitride nanotubes (BNNTs) under transverse electric fields within density-functional theory. (16,0) BNNTs with antisite, carbon substitution, single vacancy, and Stone-Wales 5775 defects are studied. Under transverse electric fields, the band gaps of the defective BNNTs are reduced, similar to the pristine ones. The energy levels of the defect states vary with the transverse electric field directions, due to the different electrostatic potential shift at the defect sites induced by the electric fields. Therefore, besides electronic structure and optical property engineering, the transverse electric field can be used to identify the defect positions in BNNTs.
The electronic structures of boron nitride nanotubes (BNNTs) doped by different organic molecules under a transverse electric field were investigated via first-principles calculations. The external field reduces the energy gap of BNNT, thus makes the
We report the stability and electronic structures of the boron nitride nanotubes (BNNTs) with diameters below 4 A by semi-empirical quantum mechanical molecular dynamics simulations and ab initio calculations. Among them (3,0), (3,1), (2,2), (4,0), (
Quantum-dot states in graphene nanoribbons (GNR) were calculated using density-functional theory, considering the effect of the electric field of gate electrodes. The field is parallel to the GNR plane and was generated by an inhomogeneous charge she
The role of defects in van der Waals heterostructures made of graphene and hexagonal boron nitride (h-BN) is studied by a combination of ab initio and model calculations. Despite the weak van der Waals interaction between layers, defects residing in
{it Ab initio} investigations of the full static dielectric response and Born effective charge of BN nanotubes (BN-NTs) have been performed for the first time using finite electric field method. It is found that the ionic contribution to the static d