Analyzing crosstalk error in the NISQ era

TL;DR

This paper investigates crosstalk errors in NISQ quantum devices, proposing protocols for characterization, mitigation strategies, and demonstrating fidelity improvements through experiments on IBM hardware.

Contribution

It introduces new protocols for crosstalk characterization and evaluates mitigation methods, providing practical insights for improving NISQ device performance.

Findings

Crosstalk significantly impacts circuit fidelity in NISQ devices.

Mitigation methods can improve fidelity despite crosstalk.

Experimental validation on IBM hardware shows fidelity gains.

Abstract

Noisy Intermediate-Scale Quantum (NISQ) hardware has unavoidable noises, and crosstalk error is a significant error source. When multiple quantum operations are executed simultaneously, the quantum state can be corrupted due to the crosstalk between gates during simultaneous operations, decreasing the circuit fidelity. In this work, we first report on several protocols for characterizing crosstalk. Then, we discuss different crosstalk mitigation methods from the hardware and software perspectives. Finally, we perform crosstalk injection experiments on the IBM quantum device and demonstrate the fidelity improvement with the crosstalk mitigation method.