Acoustoelectric current in graphene due to electron deformation potential and piezoelectric phonon couplings

Abstract

Recent studies strongly indicate that graphene can be used as a channel material for converting surface acoustic waves to acoustoelectric current, which is a resource for various exciting technological applications. On the theoretical side, studies on phonon amplification/attenuation and acoustoelectric current at low temperatures in graphene have reported approximate analytical results under exceedingly simplifying conditions using the Boltzmann transport equation. Overcoming the earlier simplifying assumptions, we investigate both numerically and analytically the governing kinetic equations for amplification/attenuation and acoustoelectric current, taking into account the piezoelectric and deformation potential electron phonon coupling mechanism in the semi classical Boltzmann transport formalism approach, and obtain analytical results that are in reasonable agreement with the reported experimental results.

Surface acoustic wave induced phenomena in two-dimensional materials

“…The SAWs modulate the electron density and even exchange energy with the electrons in 2D materials in terms of mechanical deformation potentials and piezo-electric interactions. 101 The piezo-electric fields associated with SAWs strongly interact with electrons from the adjacent surface by trapping and transporting the charge carriers at the speed of sound over macroscopic distances, generating a direct current (DC) voltage (if open-circuited) or a DC current along the drag field. This phenomena stemmed from the second-order response of the sound-induced electric fields is defined as the acousto-electric (AE) effect.…”