Generation of 95-qubit genuine entanglement and verification of symmetry-protected topological phases

TL;DR

This paper reports the generation and verification of large-scale 95-qubit and 72-qubit entangled cluster states using superconducting hardware, demonstrating their topological properties and robustness for measurement-based quantum computation.

Contribution

It introduces a method to generate and verify large-scale entangled states and demonstrates their topological phases and robustness, advancing practical quantum computing.

Findings

Generated 95-qubit and 72-qubit cluster states with high fidelity.

Verified symmetry-protected topological phases through quantum teleportation.

Demonstrated robustness of the states against symmetry-breaking perturbations.

Abstract

Symmetry-protected topological (SPT) phases are fundamental features of cluster states, serving as key resources for measurement-based quantum computation (MBQC). Generating large-scale cluster states and verifying their SPT phases are essential steps toward practical MBQC, which however still presents significant experimental challenges. In this work, we address these challenges by utilizing advanced superconducting hardware with optimized gate operations, enhanced readout fidelity, and error mitigation techniques. We successfully generate and verify 95-qubit one-dimensional and 72-qubit two-dimensional genuine entangled cluster states, achieving fidelities of $0.5603 \pm 0.0084$ and $0.5519 \pm 0.0054$, respectively. Leveraging these high-fidelity cluster states, we investigate SPT phases through quantum teleportation across all 95 qubits and demonstrate input-state-dependent robustness against symmetry-breaking perturbations, highlighting the practicality and intrinsic robustness of MBQC enabled by the SPT order. Our results represent a significant advancement in large-scale entanglement generation and topological phase simulation, laying the foundation for scalable and practical MBQC using superconducting quantum systems.