中文摘要：

我们由使用光线的紧张和联合外部电场在之字形双 walled 硼氮化物 nanotubes (DBNNT ) 在新奇乐队调整的第一原则的研究上报导。我们证明在 DBNNT 的内部、外部的墙之间的乐队排列能从类型被调节我与增加光线的紧张打 II，伴随了与一对间接乐队差距转变和实质的差距减小直接。乐队差距能被使用一个横向的电场进一步显著地减少。与光线的紧张联合电场使在 undeformed 比那各向异性、更显著的导致地的差距减小成为 DBNNT。特别地，对光线的紧张垂直的电场导致的差距变化在所有调整之中是最显著的。由在 DBNNT 的机电的联合的这些悦耳的性质将极大地在未来 nanoelectronics 充实他们的万用的应用。

英文摘要：

We report on a first-principles study of a novel band modulation in zigzag double-walled boron nitride nan- otubes （DBNNTs） by applying radial strain and coupled ex- ternal electric field. We show that the band alignment be- tween the inner and outer walls of the DBNNTs can be tuned from type I to type II with increasing radial strain, accompa- nied with a direct to indirect band gap transition and a sub- stantial gap reduction. The band gap can be further signifi- cantly reduced by applying a transverse electric field. The coupling of electric field with the radial strain makes the field-induced gap reduction being anisotropic and more re- markable than that in undeformed DBNNTs. In particular, the gap variation induced by electric field perpendicular to the radial strain is the most remarkable among all the modu-lations. These tunable properties by electromechanical cou- pling in DBNNTs will greatly enrich their versatile applica- tions in future nanoelectronics.