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A superconducting thermal switch with ultrahigh impedance for interfacing superconductors to semiconductors


A number of current approaches to quantum and neuromorphic computing use superconductors as the basis of their platform or as a measurement component, and will need to operate at cryogenic temperatures. Semiconductor systems are typically proposed as a top-level control in these architectures, with low-temperature passive components and intermediary superconducting electronics acting as the direct interface to the lowest-temperature stages. The architectures, therefore, require a low-power superconductor/semiconductor interface, which is not currently available. Here we report a superconducting switch that is capable of translating low-voltage superconducting inputs directly into semiconductor-compatible (above 1,000 mV) outputs at kelvin-scale temperatures (1 K or 4 K). To illustrate the capabilities in interfacing superconductors and semiconductors, we use it to drive a light-emitting diode in a photonic integrated circuit, generating photons at 1 K from a low-voltage input and detecting them with an on-chip superconducting single-photon detector. We also characterize our device’s timing response (less than 300 ps turn-on, 15 ns turn-off), output impedance (greater than 1 MΩ) and energy requirements (0.18 fJ m−2, 3.24 mV nW−1).

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Fig. 1: High-impedance superconducting switch overview.
Fig. 2: Driving a PIC at 1 K.
Fig. 3: Driving an 8.7 kΩ load using the switch.
Fig. 4: Critical current and inferred temperature versus input power density.

Data availability

The data that support the findings of this study are available within the paper. Additional data are available from the corresponding authors upon reasonable request.


  1. 1.

    Zhang, H. et al. Quantized Majorana conductance. Nature 556, 74–79 (2018).

    Article  Google Scholar 

  2. 2.

    King, A. D. et al. Observation of topological phenomena in a programmable lattice of 1,800 qubits. Nature 560, 456–460 (2018).

    Article  Google Scholar 

  3. 3.

    Wang, H. et al. Toward scalable boson sampling with photon loss. Phys. Rev. Lett. 120, 230502 (2018).

    Article  Google Scholar 

  4. 4.

    Shainline, J. M., Buckley, S. M., Mirin, R. P. & Nam, S. W. Superconducting optoelectronic circuits for neuromorphic computing. Phys. Rev. Appl. 7, 034013 (2017).

    Article  Google Scholar 

  5. 5.

    Slichter, D. H. et al. UV-sensitive superconducting nanowire single photon detectors for integration in an ion trap. Opt. Express 25, 8705–8720 (2017).

    Article  Google Scholar 

  6. 6.

    Silverstone, J. W., Bonneau, D., O’Brien, J. L. & Thompson, M. G. Silicon quantum photonics. IEEE J. Sel. Top. Quantum Electron. 22, 390–402 (2016).

    Article  Google Scholar 

  7. 7.

    McDermott, R. et al. Quantum–classical interface based on single flux quantum digital logic. Quant. Sci. Tech. 3, 024004 (2018).

    Article  Google Scholar 

  8. 8.

    Patra, B. et al. Cryo-CMOS circuits and systems for quantum computing applications. IEEE J. Solid-State Circuits 53, 309–321 (2018).

    Article  Google Scholar 

  9. 9.

    Ortlepp, T., Whiteley, S. R., Zheng, L., Meng, X. & Van Duzer, T. High-speed hybrid superconductor-to-semiconductor interface circuit with ultra-low power consumption. IEEE Trans. Appl. Supercond. 23, 1400104 (2013).

    Article  Google Scholar 

  10. 10.

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

    Article  Google Scholar 

  11. 11.

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

    Article  Google Scholar 

  12. 12.

    Benz, S. P. et al. One-volt Josephson arbitrary waveform synthesizer. IEEE Trans. Appl. Supercond. 25, 1300108 (2015).

    Google Scholar 

  13. 13.

    McCaughan, A. N. & Berggren, K. K. A superconducting-nanowire three-terminal electrothermal device. Nano Lett. 14, 5748–5753 (2014).

    Article  Google Scholar 

  14. 14.

    Feng, Y. J. et al. Josephson-CMOS hybrid memory with ultra-high-speed interface circuit. IEEE Trans. Appl. Supercond. 13, 467–470 (2003).

    Article  Google Scholar 

  15. 15.

    Van Duzer, T. & Kumar, S. Semiconductor-superconductor hybrid electronics. Cryogenics 30, 1014–1023 (1990).

    Article  Google Scholar 

  16. 16.

    Wei, D. et al. New Josephson-CMOS interface amplifier. IEEE Trans. Appl. Supercond. 21, 805–808 (2011).

    Article  Google Scholar 

  17. 17.

    Berggren, K. K. et al. A superconducting nanowire can be modeled by using SPICE. Super. Sci. Tech. 31, 055010 (2018).

    Article  Google Scholar 

  18. 18.

    Zhao, Q.-Y., McCaughan, A. N., Dane, A. E., Berggren, K. K. & Ortlepp, T. A nanocryotron comparator can connect single-flux-quantum circuits to conventional electronics. Super. Sci. Tech. 30, 044002 (2017).

    Article  Google Scholar 

  19. 19.

    Lee, S.-B., Hutchinson, G. D., Williams, Da, Hasko, D. G. & Ahmed, H. Superconducting nanotransistor based digital logic gates. Nanotechnology 14, 188–191 (2003).

    Article  Google Scholar 

  20. 20.

    Zhao, Q.-Y. et al. A compact superconducting nanowire memory element operated by nanowire cryotrons. Super. Sci. Tech. 31, 035009 (2018).

    Article  Google Scholar 

  21. 21.

    Buckley, S. et al. All-silicon light-emitting diodes waveguide-integrated with superconducting single-photon detectors. Appl. Phys. Lett. 111, 141101 (2017).

    Article  Google Scholar 

  22. 22.

    Clem, J. & Berggren, K. Geometry-dependent critical currents in superconducting nanocircuits. Phys. Rev. B 84, 1–27 (2011).

    Google Scholar 

  23. 23.

    Allmaras, J. P. et al. Thin-film thermal conductivity measurements using superconducting nanowires. J. Low Temp. Phys. 193, 380–386 (2018).

    Article  Google Scholar 

  24. 24.

    Sidorova, M. V. et al. Nonbolometric bottleneck in electron-phonon relaxation in ultrathin WSi films. Phys. Rev. B 97, 184512 (2018).

    Article  Google Scholar 

  25. 25.

    Marsili, F. et al. Hotspot relaxation dynamics in a current-carrying superconductor. Phys. Rev. B 93, 094518 (2016).

    Article  Google Scholar 

  26. 26.

    Shainline, J. M. et al. Circuit designs for superconducting optoelectronic loop neurons. J. Appl. Phys. 124, 152130 (2018).

    Article  Google Scholar 

  27. 27.

    McCaughan, A. N., Abebe, N. S., Zhao, Q.-Y. & Berggren, K. K. Using geometry to sense current. Nano Lett. 16, 7626–7631 (2016).

    Article  Google Scholar 

  28. 28.

    Kerman, A., Yang, J., Molnar, R., Dauler, E. & Berggren, K. Electrothermal feedback in superconducting nanowire single-photon detectors. Phys. Rev. B 79, 1–4 (2009).

    Article  Google Scholar 

  29. 29.

    Ueno, K. et al. Electric-field-induced superconductivity in an insulator. Nat. Mater. 7, 855–858 (2008).

    Article  Google Scholar 

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We thank F. Lecocq for helpful discussions and A. Lita for insight into the fabrication development. Part of this research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. J.P.A. was supported by a NASA Space Technology Research Fellowship. Support for this work was provided in part by the DARPA Defense Sciences Offices, through the DETECT programme.

Author information




A.N.M., V.B.V., S.M.B. and J.M.S. conceived and designed the experiments. A.N.M. performed the experiments. J.P.A. and A.G.K. analysed and modelled the thermal properties of the device. A.N.M. and V.B.V. fabricated the devices. A.N.M., A.N.T. and S.W.N. analysed the data.

Corresponding authors

Correspondence to A. N. McCaughan or J. M. Shainline.

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Competing interests

The authors declare US patent US10236433B1 (Thermal impedance amplifier).

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Supplementary information

Supplementary Information

Thermal transport modelling—estimation of χabs, and details of crosstalk and lateral heat transport.

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McCaughan, A.N., Verma, V.B., Buckley, S.M. et al. A superconducting thermal switch with ultrahigh impedance for interfacing superconductors to semiconductors. Nat Electron 2, 451–456 (2019).

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