Characterizing the Stability of NISQ Devices

TL;DR

This paper develops a framework and metrics to assess the stability of NISQ quantum devices, focusing on reproducibility of measurement histograms over time and across different devices.

Contribution

It introduces a moment-based distance metric and a comprehensive stability assessment methodology for NISQ devices, grounded in DiVincenzo's physical implementation requirements.

Findings

Devices with more reproducible histograms are more reliable.

The proposed metrics effectively quantify stability in both space and time.

Application to IBM's Yorktown device demonstrates practical utility.

Abstract

In this study, we focus on the question of stability of NISQ devices. The parameters that define the device stability profile are motivated by the work of DiVincenzo where the requirements for physical implementation of quantum computing are discussed. We develop the metrics and theoretical framework to quantify the DiVincenzo requirements and study the stability of those key metrics. The basis of our assessment is histogram similarity (in time and space). For identical experiments, devices which produce reproducible histograms in time, and similar histograms in space, are considered more reliable. To investigate such reliability concerns robustly, we propose a moment-based distance (MBD) metric. We illustrate our methodology using data collected from IBM's Yorktown device. Two types of assessments are discussed: spatial stability and temporal stability.