First-principles calculation of As atomic wires on a H-terminated Si(100) surface

Abstract

The atomic and electronic structures of As atomic wires, which are formed by As adsorbates around a dangling-bond wire on a H-terminated Si͑100͒, are investigated by using first-principles calculations within the local-density-functional approach. By comparing the metastable geometries of the As atomic wires with those of the Ga atomic wires previously studied, we found that As atoms have a stronger tendency to form covalent bonds. Interestingly, the most stable As configuration has an energy band with no significant dispersion as the lowest empty surface state. Electron-doping into this flat band may open up the possibility to form a ferromagnetic atomic wire. To exemplify such doping, we show that a half-filled flat band can be realized, its flatness unchanged, when K adsorbates are supplied to the As wire.

Conductance of a finite missing hydrogen atomic line on Si(001)-(2×1)-H

“…The tunneling inverse decay length of such a DB wire is smaller than polyene chains but carefully designed molecular wires are expected to give better results. Additional studies are required to clarify this issue and also whether different systems, in particular wires fabricated by deposing other atomic species near the reactive DB line, 8,30 could provide some improvements.…”

“…Moreover, the resulting reactive DB structure can presumably be used as a trap for other species, and thus to form different kinds of atomic wires. 21,8,30 In this paper, the length dependence of the conductance of a DB line stabilized on a Si͑001͒-͑2ϫ1͒-H surface is investigated in detail. The influence of the contacting pads and the finite line length are fully taken into account together with the complete atomistic and electronic structure of the line and of the supporting substrate.…”

Design of a semiconductor ferromagnet in a quantum-dot artificial crystal

“…However, it is difficult to form structures with properties of these lattices using conventional materials because Jahn-Teller distortion would destabilize the structures when the flat-band is half-filled, although some proposals have been made. [14][15][16] The eventual fabrication of QD artificial crystal materials with such striking properties is the goal of our research. In this study, we present a first-principles design of ferromagnetic materials made up of 4 nonmagnetic QD artificial atoms.…”

Role of Scanning Probes in Nanoelectronics: A Critical Review

“…Second, the conductivity of the metal wire depends critically on the deposition sites of the metal atoms as well as the species of the metal atoms. [33][34][35] It is, therefore, not clear whether the "atom wires" actually conduct, even with the atomically precise fabrication.…”