# Disordered Si:P nanostructures as switches and wires for nanodevices

## TL;DR

This paper explores the electronic properties of disordered Si:P nanostructures, demonstrating their potential as nanoswitches and nanowires by combining experimental insights with a theoretical model that accounts for atomic-scale disorder.

## Contribution

It introduces a theoretical approach using LCDO to analyze disorder effects in Si:P nanostructures and shows how gate potentials can control their conductance and localization.

## Key findings

- Disorder causes electronic localization in Si:P nanostructures.
- Gate potentials can modulate conductance and localization length.
- Theoretical model aligns with experimental transport properties.

## Abstract

Atomically precise placement of dopants in Si permits creating substitutional P nanowires by design. High-resolution images show that these wires are few atoms wide with some positioning disorder with respect to the substitutional Si structure sites. Disorder is expected to lead to electronic localization in one-dimensional (1D) - like structures. Experiments, however, report good transport properties in quasi-1D P nanoribbons. We investigate theoretically their electronic properties using an effective single-particle approach based on a linear combination of donor orbitals (LCDO), with a basis of six orbitals per donor site, thus keeping the ground state donor orbitals' oscillatory behavior due to interference among the states at the Si conduction band minima. Our model for the P positioning errors accounts for the presently achievable placement precision allowing to study the localization crossover. In addition, we show that a gate-like potential may control its conductance and localization length, suggesting the possible use of Si:P nanostructures as elements of quantum devices, such as nanoswitches and nanowires.