Transport anomaly at the ordering transition for adatoms on graphene

TL;DR

This paper investigates how the partial ordering transition of adatoms on graphene affects its electrical resistivity, revealing a non-monotonic temperature dependence linked to critical fluctuations and spectrum gap opening.

Contribution

It demonstrates the impact of Kekule mosaic ordering on graphene's resistivity and identifies a characteristic non-monotonic temperature behavior near the transition.

Findings

Kekule mosaic ordering increases graphene's sheet resistance

Critical fluctuations cause a cusp-like minimum in resistivity at T=T_c

Spectrum gap opening is associated with adatom ordering transition

Abstract

We analyze a manifestation of the partial ordering transition of adatoms on graphene in resistivity measurements. We find that Kekule mosaic ordering of adatoms increases sheet resistance of graphene, due to a gap opening in its spectrum, and that critical fluctuations of the order parameter lead to a non-monotonic temperature dependence of resistivity, with a cusp-like minimum at T=T_c.