Electron transport properties of boron nitride chains between two-dimensional metallic borophene electrodes

Recently, boron nitride (BN) chains have been made from hexagonal BN sheets. However, the BN sheet has a large band gap, which is not suitable to be used as the electrode material of BN chain-based two-dimensional (2D) electronic devices. The successful preparation of borophene sheets opens a possible way for building BN chain-based 2D devices. The borophene is a metal material with strong oxidation resistance. In particular, recent experimental results show that the borophene exists massless Dirac fermions, which makes it a suitable candidate for constructing high-speed low-dissipation devices. Here, we investigate the electron transport properties of boron nitride chains between 2D metallic borophene electrodes by using nonequilibrium Green's functions in combination with the density functional theory. Surprisingly, the BN chain displays metallic characteristic when coupled into 2D borophene electrodes. Inherent negative differential resistance behaviors can be observed in the BN chains sandwiched between 2D metallic borophene. Meanwhile, the current superposition law is studied in BN chain-based 2D circuits. Results show that the current value of BN chain-based system with parallel paths is more than twice that with a single path, which is different from Kirchhoff s circuit laws. Moreover, the effects of strain on the electron transport properties of BN chain-based 2D electronic devices are also studied.