Shot noise in Graphene with long range Coulomb interaction and the local Fermi distribution

TL;DR

This paper investigates shot noise in ballistic graphene considering long-range Coulomb interactions, revealing that interactions increase noise and frequency dependence, but the Fano factor remains unchanged at 1/3.

Contribution

It introduces a kinetic equation approach to analyze shot noise in graphene with Coulomb interactions, showing the Fano factor's invariance at degeneracy.

Findings

Shot noise increases due to Coulomb interactions.

The Fano factor at degeneracy remains 1/3.

Shot noise exhibits frequency dependence.

Abstract

We calculate the shot noise power in ballistic graphene using the kinetic equation approach based on the Keldysh technique. We find that the local energy distribution function obeys Poisson's equation, indicating a mapping into a diffusive metal system. We derive the conductance and noise including the long range Coulomb interaction to first order. We find that the shot noise increases due to interaction, leading to a frequency dependence. Furthermore, we find that the Fano factor at degeneracy is 1/3, the same as without the Coulomb interaction.