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Theoretical Fluctuations of Conductance in Stretched Monatomic Nanowire

F. Picaud·V. Pouthier·C. Girardet·E. Tosatti
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Abstract

Recent experiments showed that the last, single channel conductance step in monatomic gold contacts exhibits significant fluctuations as a function of stretching. From simulations of a stretched gold nanowire linked to deformable tips, we determine the distribution of the bond lengths between atoms forming the nanocontact and analyze its influence on the electronic conductance within a simplified single channel approach. We show that the inhomogeneous distribution of bond lengths can explain the occurrence and the 5% magnitude of conductance fluctuations below the quantum conductance unit $g_{o}= 2e^2/h$.

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F. Picaud, V. Pouthier, C. Girardet, E. Tosatti. 2003-08-26. Theoretical Fluctuations of Conductance in Stretched Monatomic Nanowire. https://doi.org/10.1016/j.susc.2003.10.040

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