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An Ultra-Stable Platform for the Study of Single-Atom Chains



Douglas T. Smith, Jon R. Pratt, Francesca M. Tavazza, Lyle E. Levine, Anne M. Chaka


We describe a surface probe instrument capable of sustaining single-atomic-bond junctions in the electronic quantum-conduction regime for tens of minutes, and present results for Au junctions that can be locked stably in n = 1 and n = 2 quantum conduction states with electrical conductivity nG0 (G0 = 2e2/h) and switched in a controlled way. The instrument measures and controls the gap formed between a probe and a flat surface with better than 5 pm long-term stability in a high-vacuum chamber at 4 K using a high-sensitivity fiber-optic interferometer that forms a Fabry-Perot cavity immediately adjacent and parallel to the probe. We also report the experimental observation of stable non-integer conduction states, along with preliminary density-functional-theory-based calculations of one-dimensional and two-dimensional Au bridges that also produce non-integer conduction states. Finally, we report the observation of novel stochastic processes related to non-ballistic electron transport through strained single-atomic-bond junctions. The instrument permits detailed study of electron transport in one-dimensional systems, and the long-term picometer stability of the junction holds great promise for application to single-molecule spectroscopy.
Journal of Applied Physics


nanomechanics, quantized conductance, nanowire, single atom chain, interferometry


Smith, D. , Pratt, J. , Tavazza, F. , Levine, L. and Chaka, A. (2010), An Ultra-Stable Platform for the Study of Single-Atom Chains, Journal of Applied Physics (Accessed December 1, 2023)
Created May 16, 2010, Updated February 19, 2017