Non-universal power laws in transport properties of one-dimensional quantum dots

TL;DR

This paper explores why experimental transport measurements in one-dimensional quantum dots deviate from universal Luttinger Liquid predictions, showing that local and global interactions influence observed power-law behaviors.

Contribution

It demonstrates that non-universal power-laws in quantum dot transport can be explained by considering local versus global interaction effects and contact properties within a Luttinger Liquid framework.

Findings

Non-universal power-laws depend on temperature range.

Contact properties significantly influence transport behavior.

Luttinger Liquid theory can explain experimental results with proper considerations.

Abstract

We investigate discrepancies between recent experimental results on transport through one-dimensional quantum dots and universal power laws predicted by an idealized Luttinger Liquid description. The temperature dependence of Coulomb blockade peaks in one-dimensional quantum dots obeys non-universal power-laws from which different values of the interaction strength can be deduced. We find that, depending on the temperature range, measurements probe local or global properties of the interaction. In particular, we investigate the role of contacting semiconductor quantum wires and nanotubes connected to leads through tunnel junctions and compare to recent experiments. We conclude that a conventional Luttinger Liquid description of the quantum wire does explain the observed behaviour if specific properties of either experimental setup are carefully taken into account.