Extraordinary electron transmission through a periodic array of quantum dots

TL;DR

This paper demonstrates that electron transmission through a periodic quantum dot array can be significantly enhanced when the electron's Fermi wavelength exceeds the array spacing, due to delocalized eigenstates caused by coherent coupling.

Contribution

It reveals a mechanism for large conductance enhancement in quantum dot arrays via delocalization from coherent coupling through leads.

Findings

Off-resonant conductance per quantum dot is increased by several orders of magnitude.

Delocalization of eigenstates is caused by coherent coupling via the electron continuum.

Enhanced conductance occurs when the Fermi wavelength exceeds the array lattice constant.

Abstract

We study electron transmission through a periodic array of quantum dots (QD) sandwiched between doped semiconductor leads. When the Fermi wavelength of tunneling electron exceeds the array lattice constant, the off-resonant per QD conductance is enhanced by several orders of magnitude relative to the single-QD conductance. The physical mechanism of the enhancement is delocalization of a small fraction of system eigenstates caused by coherent coupling of QDs via the electron continuum in the leads.