Electronic Properties of Boron Nanotubes under Uniaxial Strain: a DFT study

Electronic structures of a uniaxially stretched boron nanotube (BNT) are studied by the density functional theory (DFT) and compared with a zigzag single-walled carbon nanotube (CNT). It is verified that modifications of the electronic band structures of CNTs may be classified into three patterns depending on their helicity under the applied strain up to 20%. However, for the BNT, the partial boron bonds will be broken as the applied strain is more than 10%, indicating its poor deformation ability as compated with CNTs. Moreover, the band gap of the BNT keeps or converts to zero regardless of its chirality as the applied strain increases, which is drastically distinct from the CNT. The special behavior of the BNT implies a potential application as an excellent stress sensor.