TY - EJOUR
AU - Besedin, Ilya
AU - Kerschbaum, Michael
AU - Knoll, Jonathan
AU - Hesner, Ian
AU - Bödeker, Lukas
AU - Colmenarez, Luis
AU - Hofele, Luca
AU - Lacroix, Nathan
AU - Hellings, Christoph
AU - Swiadek, François
AU - Flasby, Alexander
AU - Panah, Mohsen Bahrami
AU - Zanuz, Dante Colao
AU - Müller, Markus
AU - Wallraff, Andreas
TI - Realizing Lattice Surgery on Two Distance-Three Repetition Codes with Superconducting Qubits
IS - arXiv:2501.04612
M1 - FZJ-2025-01517
M1 - arXiv:2501.04612
PY - 2025
N1 - 19 pages, 13 figures
AB - Quantum error correction is needed for quantum computers to be capable of fault-tolerantly executing algorithms using hundreds of logical qubits. Recent experiments have demonstrated subthreshold error rates for state preservation of a single logical qubit. In addition, the realization of universal quantum computation requires the implementation of logical entangling gates. Lattice surgery offers a practical approach for implementing such gates, particularly in planar quantum processor layouts. In this work, we demonstrate lattice surgery between two distance-three repetition-code qubits by splitting a single distance-three surface-code qubit. Using a quantum circuit fault-tolerant to bit-flip errors, we achieve an improvement in the value of the decoded $ZZ$ logical two-qubit observable compared to a similar non-encoded circuit. By preparing the surface-code qubit in initial states parametrized by a varying polar angle, we evaluate the performance of the lattice surgery operation for non-cardinal states on the logical Bloch sphere and employ logical two-qubit tomography to reconstruct the Pauli transfer matrix of the operation. In this way, we demonstrate the functional building blocks needed for lattice surgery operations on larger-distance codes based on superconducting circuits.
LB - PUB:(DE-HGF)25
UR - https://juser.fz-juelich.de/record/1038532
ER -