Weijun Zeng

Mobility fluctuations have been observed to influence 1/f noise in mesoscopic two-dimensional conductors in recent experiments. If such mobility noise can be assigned to clustering/declustering of defects/impurities, the second spectrum should also display 1/f character. In this work, we investigate the second spectrum of noise due to mobile impurities on a two-dimensional lattice both using kinetic Monte Carlo simulations (periodic boundary conditions either in one or two directions) and experiments on suspended graphene in Corbino geometry. The simulations indicate 1/fδ behavior with δ≃0.8 ± 0.15 for the second spectrum of noise, while the experiments on suspended graphene yield an exponent δ≃0.7 ± 0.3, independent of the amount of adsorbed atoms.