Localization lengths of ultrathin disordered gold and silver nanowiresA. T. Costa jr.1, R. B. Muniz2, Jisang Hong3 and R. Q. Wu3
1 Departamento de Ciências Exatas, Universidade Federal de Lavras 37200-000 Lavras, MG, Brazil
2 Instituto de Física, Universidade Federal Fluminense - 24210-340 Niterói, RJ, Brazil
3 Department of Physics and Astronomy, University of California Irvine, CA, 92697 USA
(Received 27 January 2004; accepted in final form 4 May 2004)
The localization lengths of ultrathin disordered and nanowires are estimated by calculating the wire conductances as functions of wire lengths. We study and monoatomic linear chains, and thicker wires with very small cross-sections. For the monoatomic chains we consider two types of disorder: bounded random fluctuations of the interatomic distances, and the presence of random substitutional impurities. The effect of impurity atoms on the nanowire conductance is much stronger. Our results show that electrical transport in ultrathin disordered wires may occur in the strong localization regime, and with relatively small amounts of disorder the localization lengths can be very small. The localization length dependence on wire thickness is investigated for nanowires with different impurity concentrations.
73.20.Fz - Weak or Anderson localization.
73.21.Hb - Quantum wires.
© EDP Sciences 2004