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Three-mode tunable coupler for superconducting two-qubit gates

Elena Yu. Egorova1,2,3,*, Alena S. Kazmina1,2,3, Ilya A. Simakov1,2,3, Ilya N. Moskalenko1, Nikolay N. Abramov1, Daria A. Kalacheva4,3,1, Viktor B. Lubsanov3, Alexey N. Bolgar3,4,2, Nataliya Maleeva1 et al.

Ilya S. Besedin1,2,†

  • *Contact author: yelena.egorova@phystech.edu
  • †Present address: Department of Physics, ETH Zurich, Zurich, Switzerland.
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Phys. Rev. Applied 23, 064056 – Published 25 June, 2025

DOI: https://doi.org/10.1103/2h4m-mg2p

Abstract

Building a scalable, universal, high-performance quantum processor is a formidable challenge. In particular, the problem of realizing fast, high-performance two-qubit gates of high fidelity has yet to be addressed. Here, we propose a building block for a scalable quantum processor consisting of two transmons and a tunable three-mode coupler allowing for ZZ interaction control. We experimentally demonstrate a native cz gate with a pulse duration of 60 ns, achieving a two-qubit gate fidelity above 98%, limited mostly by the qubit coherence time. Numerical simulations show that by optimizing the gate duration, the fidelity can be pushed over 99.97%.

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References (61)

  1. F. Arute, K. Arya, R. Babbush, D. Bacon, J. C. Bardin, R. Barends, R. Biswas, S. Boixo, F. G. Brandao, D. A. Buell et al., Quantum supremacy using a programmable superconducting processor, Nature 574, 505 (2019).
  2. Y. Wu, W.-S. Bao, S. Cao, F. Chen, M.-C. Chen, X. Chen, T.-H. Chung, H. Deng, Y. Du, D. Fan et al., Strong quantum computational advantage using a superconducting quantum processor, Phys. Rev. Lett. 127, 180501 (2021).
  3. Z. Chen, K. J. Satzinger, J. Atalaya, A. N. Korotkov, A. Dunsworth, D. Sank, C. Quintana, M. McEwen, R. Barends, P. V. Klimov et al., Exponential suppression of bit or phase errors with cyclic error correction, Nature 595, 383 (2021).
  4. R. Acharya, I. Aleiner, R. Allen, T. I. Andersen, M. Ansmann, F. Arute, K. Arya, A. Asfaw, J. Atalaya, R. Babbush et al., Suppressing quantum errors by scaling a surface code logical qubit, Nature 614, 676 (2023).
  5. Y. Kim, A. Eddins, S. Anand, K. X. Wei, E. Van Den Berg, S. Rosenblatt, H. Nayfeh, Y. Wu, M. Zaletel, K. Temme et al., Evidence for the utility of quantum computing before fault tolerance, Nature 618, 500 (2023).
  6. J. Koch, T. M. Yu, J. Gambetta, A. A. Houck, D. I. Schuster, J. Majer, A. Blais, M. H. Devoret, S. M. Girvin, and R. J. Schoelkopf, Charge-insensitive qubit design derived from the Cooper pair box, Phys. Rev. A 76, 042319 (2007).
  7. A. Blais, R.-S. Huang, A. Wallraff, S. M. Girvin, and R. J. Schoelkopf, Cavity quantum electrodynamics for superconducting electrical circuits: An architecture for quantum computation, Phys. Rev. A 69, 062320 (2004).
  8. F. Pan, K. Chen, and P. Zhang, Solving the sampling problem of the sycamore quantum circuits, Phys. Rev. Lett. 129, 090502 (2022).
  9. Y. A. Pashkin, T. Yamamoto, O. Astafiev, Y. Nakamura, D. V. Averin, and J. S. Tsai, Quantum oscillations in two coupled charge qubits, Nature 421, 823 (2003).
  10. F. W. Strauch, P. R. Johnson, A. J. Dragt, C. J. Lobb, J. R. Anderson, and F. C. Wellstood, Quantum logic gates for coupled superconducting phase qubits, Phys. Rev. Lett. 91, 167005 (2003).
  11. A. Dewes, F. R. Ong, V. Schmitt, R. Lauro, N. Boulant, P. Bertet, D. Vion, and D. Esteve, Characterization of a two-transmon processor with individual single-shot qubit readout, Phys. Rev. Lett. 108, 057002 (2012).
  12. B. Foxen, C. Neill, A. Dunsworth, P. Roushan, B. Chiaro, A. Megrant, J. Kelly, Z. Chen, K. Satzinger, R. Barends et al., Google AI Quantum Collaboration, Demonstrating a continuous set of two-qubit gates for near-term quantum algorithms, Phys. Rev. Lett. 125, 120504 (2020).
  13. M. Ganzhorn, G. Salis, D. J. Egger, A. Fuhrer, M. Mergenthaler, C. Müller, P. Müller, S. Paredes, M. Pechal, M. Werninghaus et al., Benchmarking the noise sensitivity of different parametric two-qubit gates in a single superconducting quantum computing platform, Phys. Rev. Res. 2, 033447 (2020).
  14. L. DiCarlo, J. M. Chow, J. M. Gambetta, L. S. Bishop, B. R. Johnson, D. I. Schuster, J. Majer, A. Blais, L. Frunzio, S. M. Girvin et al., Demonstration of two-qubit algorithms with a superconducting quantum processor, Nature 460, 240 (2009).
  15. V. Negîrneac, H. Ali, N. Muthusubramanian, F. Battistel, R. Sagastizabal, M. S. Moreira, J. F. Marques, W. J. Vlothuizen, M. Beekman, C. Zachariadis et al., High-fidelity controlled-z gate with maximal intermediate leakage operating at the speed limit in a superconducting quantum processor, Phys. Rev. Lett. 126, 220502 (2021).
  16. S. Krinner, N. Lacroix, A. Remm, A. D. Paolo, E. Genois, C. Leroux, C. Hellings, S. Lazar, F. Swiadek, J. Herrmann et al., Realizing repeated quantum error correction in a distance-three surface code, Nature 605, 669 (2022).
  17. S. A. Caldwell, N. Didier, C. A. Ryan, E. A. Sete, A. Hudson, P. Karalekas, R. Manenti, M. P. da Silva, R. Sinclair, E. Acala et al., Parametrically activated entangling gates using transmon qubits, Phys. Rev. Appl. 10, 034050 (2018).
  18. S. S. Hong, A. T. Papageorge, P. Sivarajah, G. Crossman, N. Didier, A. M. Polloreno, E. A. Sete, S. W. Turkowski, M. P. da Silva, and B. R. Johnson, Demonstration of a parametrically activated entangling gate protected from flux noise, Phys. Rev. A 101, 012302 (2020).
  19. A. O. Niskanen, K. Harrabi, F. Yoshihara, Y. Nakamura, S. Lloyd, and J. S. Tsai, Quantum coherent tunable coupling of superconducting qubits, Science 316, 723 (2007).
  20. D. C. McKay, S. Filipp, A. Mezzacapo, E. Magesan, J. M. Chow, and J. M. Gambetta, Universal gate for fixed-frequency qubits via a tunable bus, Phys. Rev. Appl. 6, 064007 (2016).
  21. X. Li, T. Cai, H. Yan, Z. Wang, X. Pan, Y. Ma, W. Cai, J. Han, Z. Hua, X. Han, Y. Wu, H. Zhang, H. Wang, Y. Song, L. Duan, and L. Sun, Tunable coupler for realizing a controlled-phase gate with dynamically decoupled regime in a superconducting circuit, Phys. Rev. Appl. 14, 024070 (2020).
  22. L. Ding, M. Hays, Y. Sung, B. Kannan, J. An, A. Di Paolo, A. H. Karamlou, T. M. Hazard, K. Azar, D. K. Kim et al., High-fidelity, frequency-flexible two-qubit fluxonium gates with a transmon coupler, Phys. Rev. X 13, 031035 (2023).
  23. M. C. Collodo, J. Herrmann, N. Lacroix, C. K. Andersen, A. Remm, S. Lazar, J.-C. Besse, T. Walter, A. Wallraff, and C. Eichler, Implementation of conditional phase gates based on tunable zz interactions, Phys. Rev. Lett. 125, 240502 (2020).
  24. J. Stehlik, D. M. Zajac, D. L. Underwood, T. Phung, J. Blair, S. Carnevale, D. Klaus, G. A. Keefe, A. Carniol, M. Kumph et al., Tunable coupling architecture for fixed-frequency transmon superconducting qubits, Phys. Rev. Lett. 127, 080505 (2021).
  25. K. Kubo and H. Goto, Fast parametric two-qubit gate for highly detuned fixed-frequency superconducting qubits using a double-transmon coupler, Appl. Phys. Lett. 122, 064001 (2023).
  26. K. Kubo, Y. Ho, and H. Goto, High-performance multiqubit system with double-transmon couplers: Toward scalable superconducting quantum computers, Phys. Rev. Appl. 22, 024057 (2024).
  27. R. Li, K. Kubo, Y. Ho, Z. Yan, Y. Nakamura, and H. Goto, Realization of high-fidelity CZ gate based on a double-transmon coupler, Phys. Rev. X 14, 041050 (2024).
  28. E. A. Sete, N. Didier, A. Q. Chen, S. Kulshreshtha, R. Manenti, and S. Poletto, Parametric-resonance entangling gates with a tunable coupler, Phys. Rev. Appl. 16, 024050 (2021).
  29. F. Yan, P. Krantz, Y. Sung, M. Kjaergaard, D. L. Campbell, T. P. Orlando, S. Gustavsson, and W. D. Oliver, Tunable coupling scheme for implementing high-fidelity two-qubit gates, Phys. Rev. Appl. 10, 054062 (2018).
  30. X. Y. Jin, K. Cicak, Z. Parrott, S. Kotler, F. Lecocq, J. Teufel, J. Aumentado, E. Kapit, and R. W. Simmonds, Fast, tunable, high fidelity CZ-gates between superconducting qubits with parametric microwave control of ZZ-coupling, arXiv:2305.02907 [quant-ph].
  31. T. Roy, Z. Li, E. Kapit, and D. Schuster, Two-qutrit quantum algorithms on a programmable superconducting processor, Phys. Rev. Appl. 19, 064024 (2023).
  32. P. Mundada, G. Zhang, T. Hazard, and A. Houck, Suppression of qubit crosstalk in a tunable coupling superconducting circuit, Phys. Rev. Appl. 12, 054023 (2019).
  33. Y. Xu, J. Chu, J. Yuan, J. Qiu, Y. Zhou, L. Zhang, X. Tan, Y. Yu, S. Liu, J. Li, F. Yan, and D. Yu, High-fidelity, high-scalability two-qubit gate scheme for superconducting qubits, Phys. Rev. Lett. 125, 240503 (2020).
  34. P. Zhao, P. Xu, D. Lan, J. Chu, X. Tan, H. Yu, and Y. Yu, High-contrast zz interaction using superconducting qubits with opposite-sign anharmonicity, Phys. Rev. Lett. 125, 200503 (2020).
  35. J. Ku, X. Xu, M. Brink, D. C. McKay, J. B. Hertzberg, M. H. Ansari, and B. L. T. Plourde, Suppression of unwanted zz interactions in a hybrid two-qubit system, Phys. Rev. Lett. 125, 200504 (2020).
  36. L. Viola and S. Lloyd, Dynamical suppression of decoherence in two-state quantum systems, Phys. Rev. A 58, 2733 (1998).
  37. V. Tripathi, H. Chen, M. Khezri, K.-W. Yip, E. Levenson-Falk, and D. A. Lidar, Suppression of crosstalk in superconducting qubits using dynamical decoupling, Phys. Rev. Appl. 18, 024068 (2022).
  38. B. K. Mitchell, R. K. Naik, A. Morvan, A. Hashim, J. M. Kreikebaum, B. Marinelli, W. Lavrijsen, K. Nowrouzi, D. I. Santiago, and I. Siddiqi, Hardware-efficient microwave-activated tunable coupling between superconducting qubits, Phys. Rev. Lett. 127, 200502 (2021).
  39. A. Noguchi, A. Osada, S. Masuda, S. Kono, K. Heya, S. P. Wolski, H. Takahashi, T. Sugiyama, D. Lachance-Quirion, and Y. Nakamura, Fast parametric two-qubit gates with suppressed residual interaction using the second-order nonlinearity of a cubic transmon, Phys. Rev. A 102, 062408 (2020).
  40. Z. Ni, S. Li, L. Zhang, J. Chu, J. Niu, T. Yan, X. Deng, L. Hu, J. Li, Y. Zhong, S. Liu, F. Yan, Y. Xu, and D. Yu, Scalable method for eliminating residual zz interaction between superconducting qubits, Phys. Rev. Lett. 129, 040502 (2022).
  41. J. Braumüller, M. Sandberg, M. R. Vissers, A. Schneider, S. Schlör, L. Grünhaupt, H. Rotzinger, M. Marthaler, A. Lukashenko, A. Dieter et al., Concentric transmon qubit featuring fast tunability and an anisotropic magnetic dipole moment, Appl. Phys. Lett. 108, 032601 (2016).
  42. J. Rahamim, T. Behrle, M. J. Peterer, A. Patterson, P. A. Spring, T. Tsunoda, R. Manenti, G. Tancredi, and P. J. Leek, Double-sided coaxial circuit QED with out-of-plane wiring, Appl. Phys. Lett. 110, 222602 (2017).
  43. J. M. Martinis, Surface loss calculations and design of a superconducting transmon qubit with tapered wiring, Npj Quantum Inf. 8, 26 (2022).
  44. S. Eun, S. H. Park, K. Seo, K. Choi, and S. Hahn, Shape optimization of superconducting transmon qubits for low surface dielectric loss, J. Phys. D: Appl. Phys. 56, 505306 (2023).
  45. P. Zhao, K. Linghu, Z. Li, P. Xu, R. Wang, G. Xue, Y. Jin, and H. Yu, Quantum crosstalk analysis for simultaneous gate operations on superconducting qubits, PRX Quantum 3, 020301 (2022).
  46. F. Marxer et al., Long-distance transmon coupler with CZ-gate fidelity above 99.8%, PRX Quantum 4, 010314 (2023).
  47. E. Egorova, A. Kazmina, and I. Moskalenko, A weakly-tunable transmon qubit with an optimized shape of the shunted capacitance, Tech. Phys. Lett. 50, 10 (2024).
  48. J. M. Chávez-Garcia, F. Solgun, J. B. Hertzberg, O. Jinka, M. Brink, and B. Abdo, Weakly flux-tunable superconducting qubit, Phys. Rev. Appl. 18, 034057 (2022).
  49. C. K. Andersen, A. Remm, S. Lazar, S. Krinner, N. Lacroix, G. J. Norris, M. Gabureac, C. Eichler, and A. Wallraff, Repeated quantum error detection in a surface code, Nat. Phys. 16, 875 (2020).
  50. G. Dolan, Offset masks for lift-off photoprocessing, Appl. Phys. Lett. 31, 337 (1977).
  51. A. Osman, J. Simon, A. Bengtsson, S. Kosen, P. Krantz, D. P Lozano, M. Scigliuzzo, P. Delsing, J. Bylander, and A. Fadavi Roudsari, Simplified Josephson-junction fabrication process for reproducibly high-performance superconducting qubits, Appl. Phys. Lett. 118, 064002 (2021).
  52. A. S. Kazmina, I. V. Zalivako, A. S. Borisenko, N. A. Nemkov, A. S. Nikolaeva, I. A. Simakov, A. V. Kuznetsova, E. Y. Egorova, K. P. Galstyan, N. V. Semenin et al., Demonstration of a parity-time-symmetry-breaking phase transition using superconducting and trapped-ion qutrits, Phys. Rev. A 109, 032619 (2024).
  53. D. C. McKay, C. J. Wood, S. Sheldon, J. M. Chow, and J. M. Gambetta, Efficient z gates for quantum computing, Phys. Rev. A 96, 022330 (2017).
  54. F. Solgun, D. P. DiVincenzo, and J. M. Gambetta, Simple impedance response formulas for the dispersive interaction rates in the effective Hamiltonians of low anharmonicity superconducting qubits, IEEE Trans. Microw. Theory Tech. 67, 928 (2019).
  55. F. Solgun and S. Srinivasan, Direct calculation of zz interaction rates in multimode circuit quantum electrodynamics, Phys. Rev. Appl. 18, 044025 (2022).
  56. M. A. Nielsen, A simple formula for the average gate fidelity of a quantum dynamical operation, Phys. Lett. A 303, 249 (2002).
  57. J. M. Chow, J. M. Gambetta, A. D. Córcoles, S. T. Merkel, J. A. Smolin, C. Rigetti, S. Poletto, G. A. Keefe, M. B. Rothwell, J. R. Rozen et al., Universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits, Phys. Rev. Lett. 109, 060501 (2012).
  58. C. J. Wood and J. M. Gambetta, Quantification and characterization of leakage errors, Phys. Rev. A 97, 032306 (2018).
  59. I. A. Simakov, G. S. Mazhorin, I. N. Moskalenko, N. N. Abramov, A. A. Grigorev, D. O. Moskalev, A. A. Pishchimova, N. S. Smirnov, E. V. Zikiy, I. A. Rodionov et al., Coupler microwave-activated controlled-phase gate on fluxonium qubits, PRX Quantum 4, 040321 (2023).
  60. Q. Ficheux, L. B. Nguyen, A. Somoroff, H. Xiong, K. N. Nesterov, M. G. Vavilov, and V. E. Manucharyan, Fast logic with slow qubits: Microwave-activated controlled-z gate on low-frequency fluxoniums, Phys. Rev. X 11, 021026 (2021).
  61. A. E. Dorogov, G. P. Fedorov, D. A. Kalacheva, A. Y. Dmitriev, A. N. Bolgar, N. N. Abramov, and O. V. Astafiev, Application of a broadband Josephson parametric amplifier, St. Petersbg. State Polytech. Univ. J.: Phys. Math. 15, 352 (2022).

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Phys. Rev. Applied 23, 064056– Published 25 June, 2025
  • Received 26 March 2025
  • Accepted 5 June 2025
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