Universal Landauer conductance in chiral symmetric 2d systems

TL;DR

This paper demonstrates that in ultraclean graphene with preserved chiral symmetry, the conductance remains quantized regardless of shape deformations, highlighting the robustness of quantum transport in such systems.

Contribution

It establishes that conductance quantization in graphene is maintained under arbitrary shape changes if chiral symmetry is preserved, emphasizing the role of symmetry in quantum transport.

Findings

Conductance is quantized in ultraclean graphene with chiral symmetry.

Smooth structural deformations do not affect conductance quantization.

Quantization is dominated by the quasi one-dimensional leads.

Abstract

We study transport properties of an arbitrarily shaped ultraclean graphene sheet, adiabatically connected to leads,composed by the same material. If the localized interactions do not destroy chiral symmetry, we show that the conductance is quantized, since it is dominated by the quasi one-dimensional leads. As an example, we show that smooth structural deformations of the graphene plane do not modify the conductance quantization.