Cutting multi-control quantum gates with ZX calculus

Abstract

Circuit cutting, the decomposition of a quantum circuit into independent partitions, has become a promising avenue towards experiments with larger quantum circuits in the noisy-intermediate scale quantum (NISQ) era. While previous work focused on cutting qubit wires or two-qubit gates, in this work we introduce a method for cutting multi-controlled Z gates. We construct a decomposition and prove the upper bound $\mathcal{O}(6^{2K})$ on the associated sampling overhead, where $K$ is the number of cuts in the circuit. This bound is independent of the number of control qubits but can be further reduced to $\mathcal{O}(4.5^{2K})$ for the special case of CCZ gates. Furthermore, we evaluate our proposal on IBM hardware and experimentally show noise resilience due to the strong reduction of CNOT gates in the cut circuits.

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Cited by in corpus (11)

• Review of Distributed Quantum Computing. From single QPU to High Performance Quantum Computing
• Doubly optimal parallel wire cutting without ancilla qubits
• Optimal joint cutting of two-qubit rotation gates
• SCIM MILQ: An HPC Quantum Scheduler
• Cutting a Wire with Non-Maximally Entangled States
• Joint Wire Cutting with Non-Maximally Entangled States
• Multithreaded parallelism for heterogeneous clusters of QPUs
• Quantum simulation in the entanglement picture
• Circuit Folding: Scalable and Graph-Based Circuit Cutting via Modular Structure Exploitation
• Joint Cutting for Hybrid Schrödinger-Feynman Simulation of Quantum Circuits
• CutReg: A loss regularizer for enhancing the scalability of QML via adaptive circuit cutting