On the relation of mechanical deformation and electrical properties of BN nanotubes

Using a novel in-situ scanning tunneling microcopy integrated into a 200Kv transmission electron microscopy, we have shown that boron nitride nanotubes (BNNTs) posses remarkable flexibility and convert from insulator to semi-conductor upon bending. To measure the electrical properties, the BNNT was bent between two gold contacts constructing a metal-semiconductor-metal circuit. The resistivity of the BNNT under bending condition was measured to be ∼460 MΩ from the experimentally recorded current-voltage data. Our finding suggests that mechanical straining can improve the electrical transport in BN nanotubes via reducing the band gap