A randomized benchmarking suite for mid-circuit measurements

TL;DR

This paper introduces a randomized benchmarking suite for mid-circuit measurements in quantum computing, enabling the detection and quantification of errors on measured and spectator qubits, and demonstrating scalability on IBM Quantum hardware.

Contribution

It presents a novel benchmarking protocol for mid-circuit measurements that assesses errors on both measured and spectator qubits, including measurement-induced and entangling errors.

Findings

Successfully detects errors on measured and spectator qubits

Quantifies measurement-induced and entangling errors

Demonstrates scalability on multiple qubits in IBM Quantum devices

Abstract

Mid-circuit measurements are a key component in many quantum information computing protocols, including quantum error correction, fault-tolerant logical operations, and measurement based quantum computing. As such, techniques to quickly and efficiently characterize or benchmark their performance are of great interest. Beyond the measured qubit, it is also relevant to determine what, if any, impact mid-circuit measurement has on adjacent, unmeasured, spectator qubits. Here, we present a mid-circuit measurement benchmarking suite developed from the ubiquitous paradigm of randomized benchmarking. We show how our benchmarking suite can be used to both detect as well as quantify errors on both measured and spectator qubits, including measurement-induced errors on spectator qubits and entangling errors between measured and spectator qubits. We demonstrate the scalability of our suite by simultaneously characterizing mid-circuit measurement on multiple qubits from an IBM Quantum Falcon device, and support our experimental results with numerical simulations. Further, using a mid-circuit measurement tomography protocol we establish the nature of the errors identified by our benchmarking suite.