Efficient Circuit Wire Cutting Based on Commuting Groups

TL;DR

This paper introduces a novel quantum circuit wire-cutting method that leverages commuting groups and MUBs-based measurement to reduce subcircuit count and measurement overhead, improving scalability for large quantum circuits.

Contribution

It proposes a new ancilla-assisted approach that transforms initializations into measurements and organizes them into commuting groups, reducing complexity in circuit reconstruction.

Findings

Significantly reduces the number of subcircuits needed.

Decreases total measurement shots for large circuits.

Demonstrates effectiveness through numerical experiments.

Abstract

Current quantum devices face challenges when dealing with large circuits due to error rates as circuit size and the number of qubits increase. The circuit wire-cutting technique addresses this issue by breaking down a large circuit into smaller, more manageable subcircuits. However, the exponential increase in the number of subcircuits and the complexity of reconstruction as more cuts are made poses a great practical challenge. Inspired by ancilla-assisted quantum process tomography and the MUBs-based grouping technique for simultaneous measurement, we propose a new approach that can reduce subcircuit running overhead. The approach first uses ancillary qubits to transform all quantum input initializations into quantum output measurements. These output measurements are then organized into commuting groups for the purpose of simultaneous measurement, based on MUBs-based grouping. This approach significantly reduces the number of necessary subcircuits as well as the total number of shots. Lastly, we provide numerical experiments to demonstrate the complexity reduction.