Ideal random quantum circuits pass the LXEB test

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Hunter-Jones, Nicholas, Haferkamp, Jonas
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866908853667364864
author Hunter-Jones, Nicholas
Haferkamp, Jonas
author_facet Hunter-Jones, Nicholas
Haferkamp, Jonas
contents We show that noiseless random quantum circuits pass the linear cross-entropy benchmark (LXEB) test with high probability. If the circuits are linear depth, and thus form unitary 4-designs, the LXEB test is passed with probability $1-O(1/\sqrt{k})$, where $k$ is the number of independently drawn samples from the output distribution of the random circuit. If the circuits are of depth $\tilde O(n^2)$, and thus form unitary $n$-designs, the LXEB test is passed with probability $1-O(e^{-k \log(n)/n})$. In proving our results, we show strong concentration of the random circuit collision probability at linear depth and establish that the tails of the distribution of random circuit output probabilities start to resemble Porter-Thomas at near-quadratic depths. Our analysis employs higher moments and high-degree approximate designs.
format Preprint
id arxiv_https___arxiv_org_abs_2602_22692
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Ideal random quantum circuits pass the LXEB test
Hunter-Jones, Nicholas
Haferkamp, Jonas
Quantum Physics
We show that noiseless random quantum circuits pass the linear cross-entropy benchmark (LXEB) test with high probability. If the circuits are linear depth, and thus form unitary 4-designs, the LXEB test is passed with probability $1-O(1/\sqrt{k})$, where $k$ is the number of independently drawn samples from the output distribution of the random circuit. If the circuits are of depth $\tilde O(n^2)$, and thus form unitary $n$-designs, the LXEB test is passed with probability $1-O(e^{-k \log(n)/n})$. In proving our results, we show strong concentration of the random circuit collision probability at linear depth and establish that the tails of the distribution of random circuit output probabilities start to resemble Porter-Thomas at near-quadratic depths. Our analysis employs higher moments and high-degree approximate designs.
title Ideal random quantum circuits pass the LXEB test
topic Quantum Physics
url https://arxiv.org/abs/2602.22692