Local probing of propagating acoustic waves in a gigahertz echo chamber
Journal article, 2012

In the same way that micro-mechanical resonators resemble guitar strings and drums, surface acoustic waves resemble the sound these instruments produce, but moving over a solid surface rather than through air. In contrast with oscillations in suspended resonators, such propagating mechanical waves have not before been studied near the quantum mechanical limits. Here, we demonstrate local probing of surface acoustic waves with a displacement sensitivity of 30 amRMS Hz^(−1/2) and detection sensitivity on the single-phonon level after averaging, at a frequency of 932 MHz. Our probe is a piezoelectrically coupled single-electron transistor, which is sufficiently fast, non-destructive and localized to enable us to track pulses echoing back and forth in a long acoustic cavity, self-interfering and ringing the cavity up and down. We project that strong coupling to quantum circuits will enable new experiments, and hybrids using the unique features of surface acoustic waves. Prospects include quantum investigations of phonon–phonon interactions, and acoustic coupling to superconducting qubits for which we present favourable estimates.




single-electron transistor

Surface acoustic wave



Martin Gustafsson

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

P.V. Santos

Paul Drude Institut fur Festkorperelektronik

Göran Johansson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Per Delsing

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Nature Physics

1745-2473 (ISSN)

Vol. 8 4 338-343

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)


Nanofabrication Laboratory

Subject Categories

Condensed Matter Physics



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