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arXiv · 1801.05270

Flip-chip gate-tunable acoustoelectric effect in graphene

J. R. Lane·L. Zhang·M. A. Khasawneh·B. N. Zhou·E. A. Henriksen·J. Pollanen
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Abstract

We demonstrate a flip-chip device for performing low-temperature acoustoelectric measurements on exfoliated two-dimensional materials. With this device, we study gate-tunable acoustoelectric transport in an exfoliated monolayer graphene device, measuring the voltage created as high-frequency surface acoustic waves dynamically drive the graphene charge carriers, the density of which we simultaneously control with a silicon back-gate. We demonstrate ambipolar dependence of the acoustoelectric signal, as expected from the sign of the graphene charge carriers. We observe a marked reduction in the magnitude of the acoustoelectric signal over a well-defined range of density in the vicinity of charge neutrality, which we attribute to a spatially heterogeneous charge-disorder landscape not directly revealed by conventional transport measurements.

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J. R. Lane, L. Zhang, M. A. Khasawneh, B. N. Zhou, E. A. Henriksen, J. Pollanen. 2018-11-20. Flip-chip gate-tunable acoustoelectric effect in graphene. https://doi.org/10.1063/1.5047211

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