title: STM study of electrical transport properties of one dimensional contacts between MnSi(~1.7) nanowires and Si(111) and (110) substrates.
abstract: We demonstrate the formation of contact barriers at the interfaces between MnSi1.7 nanowires (NWs) and Si substrates by the current-voltage (I-V) curves measured by scanning tunneling microscope with the tip contacting the NWs. The NWs on Si(110) exhibit linear reverse bias I-V curves, which suggests a parallel Ohmic surface state conductance of the Si(110) surface. The NWs on Si(111) exhibit nonlinear reverse bias I-V behavior, which indicates a considerable amount of minority carrier recombination-generation current. The NW length-dependence study of the forward bias current clearly shows that the quantitative change in NW length leads to a qualitative change in electrical transport properties. We derive a characteristic length LC ≈ 200 nm and the corresponding aspect ratio of ∼12-18 for MnSi1.7 NWs according to the variation of current density with the NW length.
authors.affiliation: Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China. Analysis and Testing Center, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
authors.forename: Xiao-Yong
authors.initials: XY
authors.lastname: Liu
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Zou