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arXiv · 2412.16116

Kramers-protected hardware-efficient error correction with Andreev spin qubits

Haoran Lu·Isidora Araya Day·Anton R. Akhmerov·Bernard van Heck·Valla Fatemi
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Abstract

We propose an architecture for bit-flip error correction of Andreev spins that is protected by Kramers' degeneracy. Specifically, we show that a coupling network of linear inductors and Andreev spin qubits results in a static Hamiltonian composed of the stabilizers of a bit-flip code. The electrodynamics of the many-body spin states also respect these stabilizers, and we show how reflectometry off a single coupled resonator can thereby accomplish their projective measurement. We further show how circuit-mediated spin couplings enable error correction operations and a complete set of single- and two-module logical quantum gates. The concept, which we dub the Ising molecule qubit (or Isene), is experimentally feasible and provides a path for compact noise-biased qubits.

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Haoran Lu, Isidora Araya Day, Anton R. Akhmerov, Bernard van Heck, Valla Fatemi. 2024-12-20. Kramers-protected hardware-efficient error correction with Andreev spin qubits. https://doi.org/10.1103/lqf3-6r5z

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