Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

A CMOS dynamic random access architecture for radio-frequency readout of quantum devices


As quantum processors become more complex, they will require efficient interfaces to deliver signals for control and readout while keeping the number of inputs manageable. Complementary metal–oxide–semiconductor (CMOS) electronics offers established solutions to signal routing and dynamic access, and the use of a CMOS platform for the qubits themselves offers the attractive proposition of integrating classical and quantum devices on-chip. Here, we report a CMOS dynamic random access architecture for readout of multiple quantum devices operating at millikelvin temperatures. Our circuit is divided into cells, each containing a control field-effect transistor and a quantum dot device, formed in the channel of a nanowire transistor. This set-up allows selective readout of the quantum dot and charge storage on the quantum dot gate, similar to one-transistor–one-capacitor (1T-1C) dynamic random access technology. We demonstrate dynamic readout of two cells by interfacing them with a single radio-frequency resonator. Our approach provides a path to reduce the number of input lines per qubit and allow large-scale device arrays to be addressed.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: Set-up and individual device characterization.
Fig. 2: Control transistor logic states.
Fig. 3: Charge retention analysis.
Fig. 4: Dynamic readout.
Fig. 5: Integration.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.


  1. 1.

    Montanaro, A. Quantum algorithms: an overview. npj Quantum Inf. 2, 15023 (2016).

    Article  Google Scholar 

  2. 2.

    Ladd, T. D. et al. Quantum computers. Nature 464, 45–53 (2010).

    Article  Google Scholar 

  3. 3.

    Neill, C. et al. A blueprint for demonstrating quantum supremacy with superconducting qubits. Science 360, 195–199 (2018).

    MathSciNet  Article  Google Scholar 

  4. 4.

    van Dijk, J. P. G. et al. The impact of classical control electronics on qubit fidelity. Preprint at (2018).

  5. 5.

    Franke, D. P., Clarke, J. S., Vandersypen, L. M. K. & Veldhorst, M. Rent’s rule and extensibility in quantum computing. Preprint at (2018).

  6. 6.

    Fowler, A. G., Mariantoni, M., Martinis, J. M. & Cleland, A. N. Surface codes: towards practical large-scale quantum computation. Phys. Rev. A 86, 032324 (2012).

    Article  Google Scholar 

  7. 7.

    Reilly, D. J. Engineering the quantum-classical interface of solid-state qubits. npj Quantum Inf. 1, 15011 (2015).

    Article  Google Scholar 

  8. 8.

    Hornibrook, J. M. et al. Cryogenic control architecture for large-scale quantum computing. Phys. Rev. Appl. 3, 024010 (2015).

    Article  Google Scholar 

  9. 9.

    Homulle, H. et al. A reconfigurable cryogenic platform for the classical control of quantum processors. Rev. Sci. Instrum. 88, 045103 (2017).

    Article  Google Scholar 

  10. 10.

    Veldhorst, M. et al. An addressable quantum dot qubit with fault-tolerant control-fidelity. Nat. Nanotechnol. 9, 981–985 (2014).

    Article  Google Scholar 

  11. 11.

    Muhonen, J. T. et al. Storing quantum information for 30 seconds in a nanoelectronic device. Nat. Nanotechnol. 9, 986–991 (2014).

    Article  Google Scholar 

  12. 12.

    Veldhorst, M. et al. A two qubit logic gate in silicon. Nature 526, 410–414 (2015).

    Article  Google Scholar 

  13. 13.

    Eng, K. et al. Isotopically enhanced triple-quantum-dot qubit. Sci. Adv. 1, e1500214 (2015).

    Article  Google Scholar 

  14. 14.

    Mi, X., Cady, J. V., Zajac, D. M., Deelman, P. W. & Petta, J. R. Strong coupling of a single electron in silicon to a microwave photon. Science 355, 156–158 (2017).

    Article  Google Scholar 

  15. 15.

    Shi, Z. et al. Fast hybrid silicon double-quantum-dot qubit. Phys. Rev. Lett. 108, 140503 (2012).

    Article  Google Scholar 

  16. 16.

    Harvey-Collard, P. et al. Coherent coupling between a quantum dot and a donor in silicon. Nat. Commun. 8, 1029 (2017).

    Article  Google Scholar 

  17. 17.

    Kawakami, E. et al. Electrical control of a long-lived spin qubit in a Si/SiGe quantum dot. Nat. Nanotechnol. 9, 666–670 (2014).

    Article  Google Scholar 

  18. 18.

    Watson, T. F. et al. A programmable two-qubit quantum processor in silicon. Nature 555, 633–637 (2018).

    Article  Google Scholar 

  19. 19.

    Zajac, D. M. et al. Resonantly driven CNOT gate for electron spins. Science 359, 439–442 (2018).

    MathSciNet  Article  Google Scholar 

  20. 20.

    Betz, A. C. et al. Dispersively detected Pauli spin-blockade in a silicon nanowire field-effect transistor. Nano Lett. 15, 4622–4627 (2015).

    Article  Google Scholar 

  21. 21.

    West, A. et al. Gate-based single-shot readout of spins in silicon. Nat. Nanotechnol. 14, 437–441 (2019).

    Article  Google Scholar 

  22. 22.

    Pakkiam, P. et al. Single-shot single-gate rf spin readout in silicon. Phys. Rev. X 8, 041032 (2018).

    Google Scholar 

  23. 23.

    Zajac, D. M., Hazard, T. M., Mi, X., Nielsen, E. & Petta, J. R. Scalable gate architecture for a one-dimensional array of semiconductor spin qubits. Phys. Rev. Appl. 6, 054013 (2016).

    Article  Google Scholar 

  24. 24.

    Takeda, K. et al. A fault-tolerant addressable spin qubit in a natural silicon quantum dot. Sci. Adv. 2, e1600694 (2016).

    Article  Google Scholar 

  25. 25.

    Yoneda, J. et al. A quantum-dot spin qubit with coherence limited by charge noise and fidelity higher than 99.9%. Nat. Nanotechnol. 13, 102–106 (2018).

    Article  Google Scholar 

  26. 26.

    Huang, W. et al. Fidelity benchmarks for two-qubit gates in silicon. Nature 569, 532–536 (2019).

    Article  Google Scholar 

  27. 27.

    Maurand, R. et al. A CMOS silicon spin qubit. Nat. Commun. 7, 13575 (2016).

    Article  Google Scholar 

  28. 28.

    Crippa, A. et al. Electrical spin driving by g-matrix modulation in spin–orbit qubits. Phys. Rev. Lett. 120, 137702 (2018).

    Article  Google Scholar 

  29. 29.

    Veldhorst, M., Eenink, H. G. J., Yang, C. H. & Dzurak, A. S. Silicon CMOS architecture for a spin-based quantum computer. Nat. Commun. 8, 1766 (2017).

    Article  Google Scholar 

  30. 30.

    Vandersypen, L. M. K. et al. Interfacing spin qubits in quantum dots and donors—hot, dense and coherent. npj Quantum Inf. 3, 34 (2017).

    Article  Google Scholar 

  31. 31.

    Li, R. et al. A crossbar network for silicon quantum dot qubits. Sci. Adv. 4, eaar3960 (2018).

    Article  Google Scholar 

  32. 32.

    Schaal, S., Barraud, S., Morton, J. J. L. & Gonzalez-Zalba, M. F. Conditional dispersive readout of a CMOS single-electron memory cell. Phys. Rev. Appl. 9, 054016 (2018).

    Article  Google Scholar 

  33. 33.

    Colless, J. I. et al. Dispersive readout of a few-electron double quantum dot with fast RF gate sensors. Phys. Rev. Lett. 110, 046805 (2013).

    Article  Google Scholar 

  34. 34.

    Gonzalez-Zalba, M. F., Barraud, S., Ferguson, A. J. & Betz, A. C. Probing the limits of gate-based charge sensing. Nat. Commun. 6, 6084 (2015).

    Article  Google Scholar 

  35. 35.

    Ahmed, I. et al. Radio-frequency capacitive gate-based sensing. Phys. Rev. Appl. 10, 014018 (2018).

    Article  Google Scholar 

  36. 36.

    Voisin, B. et al. Few-electron edge-state quantum dots in a silicon nanowire field-effect transistor. Nano Lett. 14, 2094–2098 (2014).

    Article  Google Scholar 

  37. 37.

    Mizuta, R., Otxoa, R. M., Betz, A. C. & Gonzalez-Zalba, M. F. Quantum and tunneling capacitance in charge and spin qubits. Phys. Rev. B 95, 045414 (2017).

    Article  Google Scholar 

  38. 38.

    Rossi, A., Zhao, R., Dzurak, A. S. & Gonzalez-Zalba, M. F. Dispersive readout of a silicon quantum dot with an accumulation-mode gate sensor. Appl. Phys. Lett. 110, 212101 (2017).

    Article  Google Scholar 

  39. 39.

    Al-Taie, H. et al. Cryogenic on-chip multiplexer for the study of quantum transport in 256 split-gate devices. Appl. Phys. Lett. 102, 243102 (2013).

    Article  Google Scholar 

  40. 40.

    Puddy, R. K. et al. Multiplexed charge-locking device for large arrays of quantum devices. Appl. Phys. Lett. 107, 143501 (2015).

    Article  Google Scholar 

  41. 41.

    Eichenberger, C. & Guggenbuhl, W. Charge injection of analogue CMOS switches. IEE Proc. G Circ. Devices Syst. 138, 155–159 (1991).

    Article  Google Scholar 

  42. 42.

    Wang, D. T. Modern DRAM Memory Systems: Performance Analysis and a High Performance, Power-Constrained DRAM Scheduling Algorithm. PhD thesis, Univ. Maryland (2005);

  43. 43.

    Esterli, M., Otxoa, R. M. & Gonzalez-Zalba, M. F. Small-signal equivalent circuit for double quantum dots at low-frequencies. Preprint at (2018).

  44. 44.

    Maune, B. M. et al. Coherent singlet–triplet oscillations in a silicon-based double quantum dot. Nature 481, 344–347 (2012).

    Article  Google Scholar 

  45. 45.

    Siddiqi, M. Dynamic RAM: Technology Advancements (CRC Press, 2017).

  46. 46.

    Stehlik, J. et al. Fast charge sensing of a cavity-coupled double quantum dot using a Josephson parametric amplifier. Phys. Rev. Appl. 4, 014018 (2015).

    Article  Google Scholar 

  47. 47.

    Zheng, G. et al. Rapid high-fidelity gate-based spin read-out in silicon. Preprint at (2019).

  48. 48.

    Srinivasa, V., Xu, H. & Taylor, J. M. Tunable spin–qubit coupling mediated by a multielectron quantum dot. Phys. Rev. Lett. 114, 226803 (2015).

    Article  Google Scholar 

  49. 49.

    Hornibrook, J. M. et al. Frequency multiplexing for readout of spin qubits. Appl. Phys. Lett. 104, 103108 (2014).

    Article  Google Scholar 

  50. 50.

    Franceschi, S. D. et al. SOI technology for quantum information processing. In Proc. 2016 IEEE Int. Electron Devices Meet. (IEDM) 13.4.1–13.4.4 (IEEE, 2016).

Download references


The authors thank S. Pauka, S. A. Lyon and M. Schormans for helpful discussions. This research received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 688539 ( and the Seventh Framework Programme (FP7/2007-2013) through grant agreement no. 318397, as well as from the Engineering and Physical Sciences Research Council (EPSRC) through the Centre for Doctoral Training in Delivering Quantum Technologies (EP/L015242/1) and UNDEDD (EP/K025945/1). M.F.G.Z. and A.R. acknowledge support from the Winton Programme for the Physics of Sustainability and Hughes Hall, University of Cambridge.

Author information




S.S. and M.F.G.-Z. devised the experiment. S.S., A.R. and M.F.G.-Z. performed the experiments. S.B. fabricated the sample. V.N.C.-T. and T.-Y.Y. performed measurements for low-temperature modelling. V.N.C.-T. developed and performed simulations towards integration. S.S. carried out the analysis and prepared the manuscript, with contributions from A.R., J.J.L.M. and M.F.G.-Z.

Corresponding authors

Correspondence to Simon Schaal or M. Fernando Gonzalez-Zalba.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–3, Supplementary Tables 1–2 and Supplementary equations (1)–(6).

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Schaal, S., Rossi, A., Ciriano-Tejel, V.N. et al. A CMOS dynamic random access architecture for radio-frequency readout of quantum devices. Nat Electron 2, 236–242 (2019).

Download citation

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing