Notwithstanding the discreteness of metallic constrictions, it is shown thatthe finite elasticity of stable, single-atom gold constrictions allows for acontinuous and reversible change in conductance, thereby enabling observationof channel saturation and conductance quantization. The observed channelsaturation and signature for conductance quantization is achieved bysuperposition of atomic/subatomic-scale oscillations on aretracting/approaching gold tip against a gold substrate of a scanning probe.Results also show that conductance histograms are neither suitable forevaluating the stability of atomic configurations through peak positions orpeak height nor appropriate for assessing conductance quantization. A largenumber of atomic configurations with similar conductance values give rise topeaks in the conductance histogram. The positions of the peaks and counts ateach peak can be varied by changing the conditions under which the histogramsare made. Histogram counts below 1Go cannot necessarily be assumed to arisefrom single-atom constrictions.
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