Benchmark

Cross-Entropy Benchmarking (XEB)

Linear cross-entropy on random quantum circuits · Other · 53 qubits · Cirq

Cross-entropy benchmarking (XEB) is a statistical method for evaluating quantum processor performance by measuring how well experimental output distributions of random circuits correlate with ideal distributions. Google used linear XEB to demonstrate quantum computational advantage on the 53-qubit Sycamore processor in 2019. The XEB fidelity decays exponentially with circuit depth, providing a measure of cumulative gate quality.

XEBGooglequantum-supremacySycamorerandom-circuits

Cross-entropy benchmarking (XEB) is a statistical method for evaluating quantum processor performance by measuring how well experimental output distributions of random circuits correlate with ideal distributions. Google used linear XEB to demonstrate quantum computational advantage on the 53-qubit Sycamore processor in 2019. The XEB fidelity decays exponentially with circuit depth, providing a measure of cumulative gate quality.

Key Metrics
Qubits used
53
Hardware
Google Sycamore
Key property
Exponential fidelity decay with depth
Why It Matters

The benchmark behind Google's 2019 quantum supremacy claim, establishing cross-entropy as the primary metric for quantum computational advantage demonstrations.

Hardware

Google Sycamore (superconducting)

Framework

Cirq