The aim of present study is to investigate the effect of external
electric field on the elastic and structural properties of a (3,3) armchair
boron nitride nanotube (BNNT). To accomplish this purpose,
the density functional theory (DFT) within the generalized gradient
approximation (GGA) framework is employed. The calculations are
performed employing Plane-Wave basis set and pseudopotentials.
The structural and elastic properties of armchair BNNT are predicted
in the presence of electric field parallel and perpendicular to
tube axis. The homogeneous electric fields are applied to BNNT
on the basis of the estimated optimized wave function. The
obtained results indicate that in contrast to the perpendicular field,
the external electric field along tube axis causes considerable
changes in the value of bond length and atomic positions.
Moreover, it is found that by applying electric field along tube axis
direction, Young’s modulus of BNNT decreases about 13% compared
to that in the absence of external electric field, which means
a significant reduction in the axial stiffness of BNNT