Abstract
Piezoelectric surface acoustic waves (SAWs) are powerful for investigating and controlling elementary and collective excitations in condensed matter. In semiconductor two-dimensional electron systems SAWs have been used to reveal the spatial and temporal structure of electronic states, produce quantized charge pumping, and transfer quantum information. In contrast to semiconductors, electrons trapped above the surface of superfluid helium form an ultra-high mobility, two-dimensional electron system home to strongly-interacting Coulomb liquid and solid states, which exhibit non-trivial spatial structure and temporal dynamics prime for SAW-based experiments. Here we report on the coupling of electrons on helium to an evanescent piezoelectric SAW. We demonstrate precision acoustoelectric transport of as little as ~0.01% of the electrons, opening the door to future quantized charge pumping experiments. We also show SAWs are a route to investigating the high-frequency dynamical response, and relaxational processes, of collective excitations of the electronic liquid and solid phases of electrons on helium.
| Original language | English |
|---|---|
| Article number | 4150 |
| Journal | Nature Communications |
| Volume | 12 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 1 2021 |
| Externally published | Yes |
Funding
We are grateful to M.I. Dykman, D.I. Schuster, D.G. Rees, K. Kono, J. Kitzman, and C. Mikolas for illuminating and fruitful discussions. We also thank B. Bi for technical assistance and use of the W. M. Keck Microfabrication Facility at MSU. This work was supported by the National Science Foundation via grant numbers DMR-1708331 and DMR-2003815. J.P., J.R.L., and L.Z. acknowledge the valuable support of the Cowen Family Endowment at MSU and N.R.B. acknowledges the support of a sponsored research grant from EeroQ Corp.