Minimal conductivity in bilayer graphene

TL;DR

This paper demonstrates that the minimal conductivity observed in bilayer graphene is an intrinsic property, deriving theoretical values using the Landauer formula and analyzing shot noise characteristics.

Contribution

It provides a theoretical proof that the minimal conductivity in bilayer graphene is intrinsic and calculates the Fano factor for shot noise, comparing it to single-layer graphene.

Findings

Minimal conductivity in bilayer graphene is intrinsic.

Theoretical conductivity value is e^2/2h per valley per spin.

Fano factor for shot noise is approximately 1 - 2/π.

Abstract

Using the Landauer formula approach, it is proven that minimal conductivity of order of $e^{2}/h$ found experimentally in bilayer graphene is its intrinsic property. For the case of ideal crystals, the conductivity turns our to be equal to $e^{2}/2h$ per valley per spin. A zero-temperature shot noise in bilayer graphene is considered and the Fano factor is calculated. Its value $1-2/\pi$ is close to the value 1/3 found earlier for the single-layer graphene.