# Spin relaxation 1/f noise in graphene

## TL;DR

This study measures 1/f noise in graphene's spin transport, revealing distinct noise sources and the dominance of spin-flip processes, advancing understanding of spin relaxation mechanisms.

## Contribution

First measurement of 1/f spin noise in graphene, distinguishing contact polarization noise from spin relaxation noise, and linking noise to spin-flip processes.

## Key findings

- Spin-dependent noise differs significantly from charge noise.
- Spin relaxation length and time modulate the noise magnitude.
- Spin-flip processes are the primary source of spin-dependent 1/f noise.

## Abstract

We report the first measurement of 1/f type noise associated with electronic spin transport, using single layer graphene as a prototypical material with a large and tunable Hooge parameter. We identify the presence of two contributions to the measured spin-dependent noise: contact polarization noise from the ferromagnetic electrodes, which can be filtered out using the cross-correlation method, and the noise originated from the spin relaxation processes. The noise magnitude for spin and charge transport differs by three orders of magnitude, implying different scattering mechanisms for the 1/f fluctuations in the charge and spin transport processes. A modulation of the spin-dependent noise magnitude by changing the spin relaxation length and time indicates that the spin-flip processes dominate the spin-dependent noise.