Negative Differential Resistance of Au-MgB2-Au Nanoscale Junctions

作者：Liu Fu ti; Cheng Yan^*; Chen Xiang rong

来源：Chinese Journal of Chemical Physics, 2014, 27(4): 407-411.

DOI：10.1063/1674-0068/27/04/407-411

• Electronic transport
• MgB2 atomic chain
• Negative differential resistance

The electron transport of linear atomic chain of MgB2 sandwiched between Au(100) electrodes was investigated by using the density functional theory with the non-equilibrium Green's function method. We have calculated the corresponding cohesion energy and conductance of junctions in different distance. It is found that, at the equilibrium position, the Au- B bond-length is 1.90 angstrom, the B-Mg bond-length is 2.22 angstrom, and the equilibrium conductance is 0.51G(0) (G(0)=2e(2)/h). The transport channel is almost formed by the pi antibonding orbitals, which was made up of the p(x) and p(y) orbital electrons of B and Mg atoms. In the voltage range of -1.5 to 1.5 V, the junctions show the metallic behaviors. When the voltage is larger than 1.5 V, the current decreases gradually and then negative differential resistance appears almost symmetrically on both positive and negative bias.

• 出版日期2014-8
• 单位宜宾学院; 四川大学