Fractal Conductance Fluctuations in Gold--Nanowires

TL;DR

This paper investigates fractal conductance fluctuations in gold nanowires, revealing a power-law behavior in conductance variance indicative of fractal patterns, influenced by wire length and chaotic electron trajectories.

Contribution

It provides the first detailed analysis linking fractal conductance fluctuations to chaotic trajectories in gold nanowires of varying lengths.

Findings

Conductance fluctuations follow a power-law with respect to magnetic field difference.

Fractal behavior becomes more pronounced in longer nanowires.

Long-lived states from chaotic trajectories influence conductance patterns.

Abstract

A detailed analysis of magneto-conductance fluctuations of quasiballistic gold-nanowires of various lengths is presented. We find that the variance $<(\Delta G)^2> = < (G(B)-G(B+\Delta B))^2>$ when analyzed for $\Delta B$ much smaller than the correlation field $B_c$ varies according to $<(\Delta G)^2>\propto \Delta B^{\gamma}$ with $\gamma < 2$ indicating that the graph of $G$ vs. $B$ is fractal. We attribute this behavior to the existence of long-lived states arising from chaotic trajectories trapped close to regular classical orbits. We find that $\gamma$ decreases with increasing length of the wires.