Determining the quantum-coherent to semiclassical transition in atomic-scale quasi-one-dimensional metals

Abstract

Individual dopants in semiconductors are attracting considerable attention due to the prospect of using them in a wide range of applications. In particular, phosphorus donors in silicon have attracted significant interest owing to their weak interaction with the host crystal. However, harnessing their attributes toward the construction of scalable circuitry will require low resistive interconnects at a comparable scale as the dopant atoms. In this Rapid Communication, the authors investigate the transition from quantum coherent to the semiclassical diffusive transport in a 4.6-nm quasi-one-dimensional Si:P metal wire. Analyzing the temperature dependence of universal conductance fluctuations (UCF) the authors show that electron transport evolves from a quantum coherent to a semiclassical regime at temperatures as low as ~4 K and confirm that concepts of UCF and weak localization remain valid in metallic conductors at the atomic-scale.