Conductivities of quasi-one-dimensional metallic atomic-chain (AC) arrays of Si(553)-Au and $\mathrm{Si}\left(111\right)4\times 1\text{−}\mathrm{In}$ surfaces were measured by a rotational square micro-four-point probe method. This method provided the conductivity along the ACs $\left({\sigma }_{\Vert }\right)$ and that across them $\left({\sigma }_{\perp }\right)$ separately. While the measured ${\sigma }_{\Vert }$ of the $4\times 1\text{−}\mathrm{In}$ was nearly half of ${\sigma }_{\Vert }$ expected from the surface-state band structure, the ${\sigma }_{\Vert }$ of the Si(553)-Au was more than 1 order of magnitude smaller than the value expected from the bands. This was attributed to dense intrinsic point defects on the Si(553)-Au. We demonstrated that point defects on the ACs really decreased the ${\sigma }_{\Vert }$ value by intentionally introducing defects on the $4\times 1\text{−}\mathrm{In}$ with oxygen adsorption.

• Received 17 June 2007

DOI:https://doi.org/10.1103/PhysRevB.76.195418