Abstract
An enduring challenge in constructing mechanical-oscillator-based hybrid quantum systems is to ensure engineered coupling to an auxiliary degree of freedom and maintain good mechanical isolation from the environment, that is, low quantum decoherence, consisting of thermal decoherence and dephasing. Here we overcome this challenge by introducing a superconducting-circuit-based optomechanical platform that exhibits low quantum decoherence and has a large optomechanical coupling, which allows us to prepare the quantum ground and squeezed states of motion with high fidelity. We directly measure a thermal decoherence rate of 20.5 Hz (corresponding to T1 = 7.7 ms) as well as a pure dephasing rate of 0.09 Hz, yielding a 100-fold improvement in the quantum state lifetime compared with prior optomechanical systems. This enables us to reach a motional ground-state occupation of 0.07 quanta (93% fidelity) and realize mechanical squeezing of –2.7 dB below the zero-point fluctuation. Furthermore, we observe the free evolution of the mechanical squeezed state, preserving its non-classical nature over millisecond timescales. Such ultralow quantum decoherence not only increases the fidelity of quantum control and measurement of macroscopic mechanical systems but may also benefit interfacing with qubits, and places the system in a parameter regime suitable for tests of quantum gravity.
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Data availability
The data used to produce the plots within this paper are available via Zenodo at https://doi.org/10.5281/zenodo.7833893. All other data used in this study are available from the corresponding authors on reasonable request. Source data are provided with this paper.
Code availability
The code used to produce the plots within this paper is available via Zenodo at https://doi.org/10.5281/zenodo.7833893.
References
Aasi, J. et al. Enhanced sensitivity of the LIGO gravitational wave detector by using squeezed states of light. Nat. Photon. 7, 613–619 (2013).
Mason, D., Chen, J., Rossi, M., Tsaturyan, Y. & Schliesser, A. Continuous force and displacement measurement below the standard quantum limit. Nat. Phys. 15, 745–749 (2019).
Whittle, C. et al. Approaching the motional ground state of a 10-kg object. Science 372, 1333–1336 (2021).
Pechal, M., Arrangoiz-Arriola, P. & Safavi-Naeini, A. H. Superconducting circuit quantum computing with nanomechanical resonators as storage. Quantum Sci. Technol. 4, 015006 (2018).
Wallucks, A., Marinković, I., Hensen, B., Stockill, R. & Gröblacher, S. A quantum memory at telecom wavelengths. Nat. Phys. 16, 772–777 (2020).
Fiaschi, N. et al. Optomechanical quantum teleportation. Nat. Photon. 15, 817–821 (2021).
Marinković, I. et al. Optomechanical bell test. Phys. Rev. Lett. 121, 220404 (2018).
Carney, D. et al. Mechanical quantum sensing in the search for dark matter. Quantum Sci. Technol. 6, 024002 (2021).
Manley, J., Chowdhury, M. D., Grin, D., Singh, S. & Wilson, D. J. Searching for vector dark matter with an optomechanical accelerometer. Phys. Rev. Lett. 126, 061301 (2021).
Aspelmeyer, M., Kippenberg, T. J. & Marquardt, F. Cavity optomechanics. Rev. Mod. Phys. 86, 1391 (2014).
Clerk, A., Lehnert, K., Bertet, P., Petta, J. & Nakamura, Y. Hybrid quantum systems with circuit quantum electrodynamics. Nat. Phys. 16, 257–267 (2020).
Chu, Y. & Gröblacher, S. A perspective on hybrid quantum opto- and electromechanical systems. Appl. Phys. Lett. 117, 150503 (2020).
Wollman, E. E. et al. Quantum squeezing of motion in a mechanical resonator. Science 349, 952–955 (2015).
Pirkkalainen, J.-M., Damskägg, E., Brandt, M., Massel, F. & Sillanpää, M. A. Squeezing of quantum noise of motion in a micromechanical resonator. Phys. Rev. Lett. 115, 243601 (2015).
Lecocq, F., Clark, J. B., Simmonds, R. W., Aumentado, J. & Teufel, J. D. Quantum nondemolition measurement of a nonclassical state of a massive object. Phys. Rev. X 5, 041037 (2015).
Reed, A. et al. Faithful conversion of propagating quantum information to mechanical motion. Nat. Phys. 13, 1163–1167 (2017).
Chu, Y. et al. Creation and control of multi-phonon Fock states in a bulk acoustic-wave resonator. Nature 563, 666–670 (2018).
Mirhosseini, M., Sipahigil, A., Kalaee, M. & Painter, O. Superconducting qubit to optical photon transduction. Nature 588, 599–603 (2020).
Andrews, R. W. et al. Bidirectional and efficient conversion between microwave and optical light. Nat. Phys. 10, 321–326 (2014).
Kotler, S. et al. Direct observation of deterministic macroscopic entanglement. Science 372, 622–625 (2021).
Rossi, M., Mason, D., Chen, J., Tsaturyan, Y. & Schliesser, A. Measurement-based quantum control of mechanical motion. Nature 563, 53–58 (2018).
Delaney, R. D., Reed, A. P., Andrews, R. W. & Lehnert, K. W. Measurement of motion beyond the quantum limit by transient amplification. Phys. Rev. Lett. 123, 183603 (2019).
Gardiner, C. & Zoller, P. Quantum Noise: A Handbook of Markovian and Non-Markovian Quantum Stochastic Methods with Applications to Quantum Optics (Springer Science & Business Media, 2004).
MacCabe, G. S. et al. Nano-acoustic resonator with ultralong phonon lifetime. Science 370, 840–843 (2020).
Magrini, L. et al. Real-time optimal quantum control of mechanical motion at room temperature. Nature 595, 373–377 (2021).
Tebbenjohanns, F., Mattana, M. L., Rossi, M., Frimmer, M. & Novotny, L. Quantum control of a nanoparticle optically levitated in cryogenic free space. Nature 595, 378–382 (2021).
Delić, U. et al. Cooling of a levitated nanoparticle to the motional quantum ground state. Science 367, 892–895 (2020).
Piotrowski, J. et al. Simultaneous ground-state cooling of two mechanical modes of a levitated nanoparticle. Nat. Phys. 19, 1009–1013 (2023).
Teufel, J. D. et al. Sideband cooling of micromechanical motion to the quantum ground state. Nature 475, 359–363 (2011).
Ockeloen-Korppi, C. et al. Stabilized entanglement of massive mechanical oscillators. Nature 556, 478–482 (2018).
Palomaki, T., Teufel, J., Simmonds, R. & Lehnert, K. W. Entangling mechanical motion with microwave fields. Science 342, 710–713 (2013).
Palomaki, T., Harlow, J., Teufel, J., Simmonds, R. & Lehnert, K. W. Coherent state transfer between itinerant microwave fields and a mechanical oscillator. Nature 495, 210–214 (2013).
Bernier, N. R. et al. Nonreciprocal reconfigurable microwave optomechanical circuit. Nat. Commun. 8, 604 (2017).
Gely, M. F. & Steele, G. A. Phonon-number resolution of voltage-biased mechanical oscillators with weakly anharmonic superconducting circuits. Phys. Rev. A 104, 053509 (2021).
Gely, M. F. & Steele, G. A. Superconducting electro-mechanics to test Diósi–Penrose effects of general relativity in massive superpositions. AVS Quantum Sci. 3, 035601 (2021).
Liu, Y., Mummery, J., Zhou, J. & Sillanpää, M. A. Gravitational forces between nonclassical mechanical oscillators. Phys. Rev. Appl. 15, 034004 (2021).
Seis, Y. et al. Ground state cooling of an ultracoherent electromechanical system. Nat. Commun. 13, 1507 (2022).
Liu, Y. et al. Optomechanical anti-lasing with infinite group delay at a phase singularity. Phys. Rev. Lett. 127, 273603 (2021).
Tsaturyan, Y., Barg, A., Polzik, E. S. & Schliesser, A. Ultracoherent nanomechanical resonators via soft clamping and dissipation dilution. Nat. Nanotechnol. 12, 776–783 (2017).
Leibfried, D., Blatt, R., Monroe, C. & Wineland, D. Quantum dynamics of single trapped ions. Rev. Mod. Phys. 75, 281 (2003).
Gaebler, J. P. et al. High-fidelity universal gate set for 9Be+ ion qubits. Phys. Rev. Lett. 117, 060505 (2016).
Schmid, S., Jensen, K., Nielsen, K. & Boisen, A. Damping mechanisms in high-Q micro and nanomechanical string resonators. Phys. Rev. B 84, 165307 (2011).
Weinstein, A. et al. Observation and interpretation of motional sideband asymmetry in a quantum electromechanical device. Phys. Rev. X 4, 041003 (2014).
Macklin, C. et al. A near–quantum-limited Josephson traveling-wave parametric amplifier. Science 350, 307–310 (2015).
Kronwald, A., Marquardt, F. & Clerk, A. A. Arbitrarily large steady-state bosonic squeezing via dissipation. Phys. Rev. A 88, 063833 (2013).
Acknowledgements
We thank MIT Lincoln Laboratory and W. D. Oliver for providing the Josephson travelling-wave parametric amplifier. We thank A. Arabmoheghi for helpful discussions on the theory of mechanical dissipation. This work was supported by the EU H2020 research and innovation programme under grant no. 101033361 (QuPhon), and from the European Research Council (ERC) grant no. 835329 (ExCOM-cCEO). This work was also supported by the Swiss National Science Foundation (SNSF) under grant no. NCCR-QSIT:51NF40_185902 and no. 204927. All the devices were fabricated in the Center of MicroNanoTechnology (CMi) at EPFL.
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Contributions
A.Y. conceived the experiment. S.K., M.C. and A.Y. developed the theory. A.Y. designed and simulated the devices. A.Y. developed the fabrication process with assistance from M.C. M.C. and A.Y. fabricated the samples. A.Y. and M.C. developed the experimental setup. The measurement was performed by A.Y. and M.C., with assistance from S.K. The data analysis was performed by A.Y. with assistance from S.K. S.K. introduced the phonon number calibration based on sideband asymmetry and conducted the numerical simulation for extracting the mechanical dephasing. The manuscript was written by A.Y., S.K., M.C. and T.J.K. T.J.K. supervised the project.
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Extended data
Extended Data Fig. 1 Overview on the fabrication technique for highly coherent circuit optomechanics.
The main steps of the process consists of etching a trench in the substrate followed by deposition of a sacrificial layer, planarization, top layer definition, release, and finally cool down. Due to the compressive stresses, the top plate may buckle up after the release. However, the drumhead shrinks and flattens at cryogenic temperatures, resulting in a controllable gap size.
Extended Data Fig. 2 Free evolution of a mechanical squeezed state.
a, Quadrature variances and average phonon number of a squeezed state as a function of the free-evolution time. The blue, red and purple circles are the data for the quadrature variances in the squeezed and anti-squeezed axes, and the average phonon number, respectively. The black dotted lines are linear fits, while the green lines are the numerical simulation results. Error bars are corresponding to standard deviations. b, The difference of the thermal decoherence rates for the quadrature variances in the squeezed and anti-squeezed axes as a function of the pure dephasing rate. The green line shows the numerical simulation results, while the blue line is the experimentally obtained value. The shaded regions show the errors, respectively.
Supplementary information
Supplementary Information
Supplementary Figs. 1–20, Tables 1 and 2 and References.
Source data
Source Data Fig. 1
Source data for ring-down and frequency fluctuation.
Source Data Fig. 2
Source data for sideband asymmetry.
Source Data Fig. 3
Source data for optomechanical amplification.
Source Data Fig. 4
Source data for squeezing.
Source Data Extended Data Fig. 2
Source data for dephasing rate extraction.
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Youssefi, A., Kono, S., Chegnizadeh, M. et al. A squeezed mechanical oscillator with millisecond quantum decoherence. Nat. Phys. 19, 1697–1702 (2023). https://doi.org/10.1038/s41567-023-02135-y
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DOI: https://doi.org/10.1038/s41567-023-02135-y
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