Realizing three logical qubits in a qLDPC code with superconducting circuits, Part 1: Theory

ORAL

Abstract

Recent work has shown that quantum error correcting codes with non-local connectivity may significantly reduce the qubit overhead required to reach algorithmically relevant logical error rates [1]. However, realizing these so-called quantum low-density parity-check (qLDPC) codes with superconducting qubits seems challenging since this platform most naturally supports 2D local connectivities. In this two-part talk, we outline our theoretical and experimental efforts toward realizing a small-scale qLDPC code using superconducting qubits, encoding three logical qubits at distance-two with only six data qubits and two long-range connections. The results presented in this talk, combined with discussions on how our techniques extend to larger code architectures, provide evidence for a path to low-overhead quantum error correction with superconducting qubits.

Part 1 will theoretically introduce our novel [[6,3,2]] code, featuring X, Z, and Y stabilizers, which are measured repeatedly. We discuss the implications of operating on three logical qubits within one code block and present schemes such as logical cluster-state preparation and logical teleportation between our three logical qubits.



[1] S. Bravyi, et al., Nature, 2024

*This research was sponsored in part by IARPA and the Army Research Office, under the Entangled Logical Qubits program, and was accomplished under Cooperative Agreement Number W911NF-23-2-0212; in part by the U.S. Army Research Office (ARO) Multidisciplinary University Research Initiative (MURI) W911NF-18-1-0218; and in part under Air Force Contract No. FA8702-15-D-0001. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the U.S. Government.

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Presenters

  • Lukas Pahl

    • Massachusetts Institute of Technology

Authors

  • Lukas Pahl

    • Massachusetts Institute of Technology

  • David Pahl

    • Massachusetts Institute of Technology

  • Max Hays

    • MIT
    • Massachusetts Institute of Technology (MIT)
    • Massachusetts Institute of Technology

  • Daniel Miller

    • Freie Universität Berlin

  • William P Banner

    • Massachusetts Institute of Technology

  • Gabriel Cutter

    • Massachusetts Institute of Technology

  • Vaishnavi Addala

    • Massachusetts Institute of Technology

  • Michael Gingras

    • MIT Lincoln Laboratory

  • Jeffrey M Knecht

    • MIT Lincoln Laboratory

  • Bethany M Niedzielski

    • MIT Lincoln Laboratory

  • Hannah M Stickler

    • MIT Lincoln Laboratory

  • Mollie E Schwartz

    • MIT Lincoln Laboratory
    • Lincoln Laboratory, Massachusetts Institute of Technology

  • Kyle Serniak

    • MIT Lincoln Laboratory
    • Lincoln Laboratory, Massachusetts Institute of Technology

  • Jeffrey A Grover

    • Massachusetts Institute of Technology

  • Jens Eisert

    • Freie Universität Berlin
    • FU Berlin

  • William D Oliver

    • Massachusetts Institute of Technology
    • Massachusetts Institute of Technology (MIT)