Electron Transport Through a 1D Chain of Dopant-Based Quantum Dots

TL;DR

This paper investigates electron transport in a 1D chain of dopant-based quantum dots using the extended Fermi-Hubbard model, revealing insights into charge distribution, level interactions, and plasmonic behavior relevant for semiconductor physics.

Contribution

It applies the extended Fermi-Hubbard model to analyze charge transport and plasmonic phenomena in dopant-based quantum dot chains, highlighting effects of long-range interactions.

Findings

Charge density distribution depends on hopping and Coulomb parameters.

Level repulsion influences energy levels at anticrossings.

Identifies perturbations linked to one-dimensional system behavior.

Abstract

Strongly interacting electron systems can provide insight into quantum many-body phenomena, such as Mott insulating behavior and spin liquidity, facilitating semiconductor optimization. The Fermi-Hubbard model is the prototypical model used to study such systems. Recent research, however, has shown that the extended Fermi-Hubbard model, which accounts for long-range interactions, is more accurate, especially for systems far from half-filling. In this study, we use the extended Fermi-Hubbard model to mathematically analyze charge transport through a lattice of quantum dots. One-dimensional chains with spinless electrons and source-drain bias are observed, focusing on the transition between the ground state and the first excited state. Level repulsion decreases the expected energy levels of anticrossings as the hopping onto the chain tends to the hopping within the chain. The distribution of charge density along the chain is characterized in terms of the hopping, nuclear, and Coulomb parameters and novel plasmonic behavior is analyzed. Minor perturbations in electron transport are identified, corresponding to the one-dimensional nature of the observed systems. This research will lead to a better understanding of electron behavior in silicon-doped semiconductors, like the formation of correlation-induced band gaps, and open the door to using the extended Fermi-Hubbard model as a more accurate alternative to study quantum many-body systems.