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We demonstrate the directed control of charge carriers in graphene using the electric field that accompanies the propagation of surface acoustic waves (SAWs) on a piezoelectric surface. Graphene grown by chemical vapor deposition was transferred to the surface of lithium niobate, allowing its direct integration with interdigital transducers used for SAW generation and detection. Radio frequency (RF) signal applied to the transducers at their resonant frequency was found to generate a direct current flow by the transport of p-type charge carriers. The acoustically induced current scales linearly with the applied RF power and can be observed even in presence of a counter-flow current induced by an applied bias.

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We have studied the effect of both long-and short-range disorder on frequency scaling of the diagonal magnetoconductivity σ xx in the integer quantum Hall effect regime of two-dimensional electrons confined to Al x Ga 1-x As/Al 0.33 Ga 0.67 As single heterostructures for two Al concentrations, x. Within the frequency range 100 MHz f 20 GHz and for a temperature T = 35 mK, we found that the frequency scaling exponent c changes from 0.6 ± 0.05 for a GaAs/Al 0.33 Ga 0.67 As heterostructure, where the disorder is dominated by long-range ionized impurity potentials, to c = 0.42 ± 0.06 for Al 0.015 Ga 0.985 As/Al 0.33 Ga 0.67 As heterostructures, where the dominant contribution to the disorder is from short-range alloy potential fluctuations. This value of c allows us to estimate the dynamical scaling exponent as z = 1 ± 0.13.