Quantum transport in metallic nanowires fabricated by electrochemical deposition/dissolution

Abstract

A nonmechanical method for fabricating a metallic narrow constriction between two electrodes using electrochemical deposition is described. The width of the constriction can be adjusted by slowly dissolving metal atoms away or redepositing atoms onto the constriction which can be controlled flexibly by the electrodes’ potentials. Well-defined plateaus near the integer numbers of the conductance quantum have been observed in these constrictions at room temperature. Since no mechanical movements are involved, this method has the potential of fabricating nanoconstrictions with long term stability.

Molecular three-terminal devices: fabrication and measurements

“…These include electromigration 2 in which a metal wire is broken with an electric field, shadow evaporation 3 and electrochemical techniques. [4][5][6][7] In all these cases, nanoscale gaps are produced in metallic wires that are bridged by molecules, sitting on top of a gate electrode separated by an oxide layer. The gate electrode electrostatically modifies the potential of the molecular orbitals independently from the bias voltage.…”

Electrochemical properties of atomic-scale metal wires

“…During the separation, a metal neck is formed between the two electrodes and then stretched into an atomically thin wire with quantized conductance before it is completely broken. The second method, developed by us recently, is to electrochemically fabricate the wires [8,9]. Recent transmission electron microscopy has directly confirmed that a metal wire with quantized conductance consists of a string of a few metal atoms [10,11].…”

From Metal Cluster to Metal Nanowire: A Topological Analysis of Electron Density and Band Structure Calculation

“…Still much effort has been devoted to construct metallic connection in molecular scale. With the rapidly advanced fabrication technology, metallic nanowires have been created by mechanically breaking a fine metal wire [6], by separating a tip and a flat substrate [7][8][9], or two macroscopic electrodes in contact [10], by anodizing Al nanowires with an atomic force microscope [11], and by electrochemical deposition [12,13]. All the methods mentioned above have difficulties in maintaining the uniformity in both the detailed atomic scale size and structure of the nanowires.…”