Spin relaxation 1/f noise in graphene

We report the rst 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 ltered out using the cross-correlation method, and the noise originated from the spin relaxation processes. The noise magnitude for spin and charge transport diers by three orders of magnitude, implying dierent 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-ip processes dominate the spin-dependent noise.