A quantum electromechanical interface for long-lived phonons
Creators
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1.
California Institute of Technology
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2.
Jet Propulsion Lab
Abstract
In single crystals, the suppression of intrinsic loss channels at low temperatures leads to exceptionally long mechanical lifetimes. Quantum electrical control of such long-lived mechanical oscillators would enable the development of phononic memory elements, sensors and transducers. The integration of piezoelectric materials is one approach to introducing electrical control, but the challenges of combining heterogeneous materials lead to severely limited phonon lifetimes. Here we present a non-piezoelectric silicon electromechanical system capable of operating in the gigahertz frequency band. Relying on a driving scheme based on electrostatic fields and the kinetic inductance effect in disordered superconductors, we demonstrate a parametrically enhanced electromechanical coupling of g/2π = 1.1 MHz, sufficient to enter the strong-coupling regime with a cooperativity of C = 1,200. In our best devices, we measure mechanical quality factors approaching Q ≈ 10⁷, measured at low-phonon numbers and millikelvin temperatures. Despite using strong electrostatic fields, we find the cavity mechanics system in the quantum ground state, verified by thermometry measurements. Simultaneously achieving ground-state operation, long mechanical lifetimes and strong coupling sets the stage for employing silicon electromechanical devices in hybrid quantum systems and as a tool for studying the origins of acoustic loss in the quantum regime.
Copyright and License
© The Author(s), under exclusive licence to Springer Nature Limited 2023.
Acknowledgement
We thank O. Painter and M. Kalaee for the fruitful discussions that led to the conception of this work. This work was supported by start-up funds from the EAS division at Caltech, National Science Foundation (grant no. 2137776), and a KNI-Wheatley scholarship. This material is based on work supported by the US Department of Energy Office of Science National Quantum Information Science Research Centers. C.J. acknowledges support from an IQIM/AWS Postdoctoral Fellowship.
Contributions
Contributions. A.B. and M.M. came up with the concept and designed the experiment. A.B. and H.Z. worked on the fabrication of the devices, conducted the measurements and analysed the data. C.J. established the measurement set-up. H.G.L. and P.K.D. performed the deposition of superconducting thin films. A.B., C.J. and M.M. wrote the paper with input from all authors. M.M. supervised the project.
Data Availability
Data availability. The datasets utilized to generate the plots in the paper are available on Zenodo (https://doi.org/10.5281/zenodo.7793615). All other data generated and/or analysed during the current study are available from the corresponding author upon reasonable request.
Conflict of Interest
The authors declare no competing interests.
Files
41567_2023_2080_MOESM1_ESM.pdf
Additional details
Related works
- Describes
- Caltech News: https://www.caltech.edu/about/news/new-device-opens-door-to-storing-quantum-information-as-sound-waves (URL)
- Dataset: 10.5281/zenodo.7793615 (DOI)
- Journal Article: https://rdcu.be/e0Bcg (ReadCube)
- Is new version of
- Discussion Paper: arXiv:2207.10972 (arXiv)
Funding
- Caltech Division of Engineering and Applied Science
- NSF
- OMA-2137776
- Kavli Nanoscience Institute
- Q-NEXT
- Institute for Quantum Information and Matter (IQIM)
- AWS Center for Quantum Computing
Dates
- Available
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2023-06-22Published
Caltech Custom Metadata
- Caltech groups
- AWS Center for Quantum Computing , Institute for Quantum Information and Matter , Kavli Nanoscience Institute
- Publication Status
- Published