Saved in:
Bibliographic Details
Main Authors: Denzler, Janek, Varona, Santiago, Guaita, Tommaso, Carrasco, Jose
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2501.11688
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908479968509952
author Denzler, Janek
Varona, Santiago
Guaita, Tommaso
Carrasco, Jose
author_facet Denzler, Janek
Varona, Santiago
Guaita, Tommaso
Carrasco, Jose
contents In this paper, we introduce a class of highly entangled real quantum states that cannot be approximated by circuits with $\log$-many non-Clifford gates and prove that Bell sampling enables efficient cross-device verification (or distributed inner product estimation) for these states. That is, two remote parties can estimate the inner product ${\rm tr}(ρσ)$, each having black-box access to copies of a state $ρ$ (or respectively $σ$) in this class. This is significant because it is clear that this task can be achieved in those cases (such as low entanglement or low non-Clifford gate count) where one can independently learn efficient classical descriptions of each state using established techniques and share the description to compute the overlap. Instead, our results demonstrate that this is possible even in more complex scenarios where these "learn and share" methods are insufficient. Our proposal is scalable, as it just requires a number of two-copy Bell measurements and single-copy Pauli measurements that grows polynomially with both the number of qubits and the desired inverse-error, and can be implemented in the near term. Moreover, the required number of samples can be efficiently experimentally determined by the parties in advance, and our findings are robust against preparation errors. We anticipate that these results could have applications in quantum cryptography and verification.
format Preprint
id arxiv_https___arxiv_org_abs_2501_11688
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Highly-entangled, highly-doped states that are efficiently cross-device verifiable
Denzler, Janek
Varona, Santiago
Guaita, Tommaso
Carrasco, Jose
Quantum Physics
In this paper, we introduce a class of highly entangled real quantum states that cannot be approximated by circuits with $\log$-many non-Clifford gates and prove that Bell sampling enables efficient cross-device verification (or distributed inner product estimation) for these states. That is, two remote parties can estimate the inner product ${\rm tr}(ρσ)$, each having black-box access to copies of a state $ρ$ (or respectively $σ$) in this class. This is significant because it is clear that this task can be achieved in those cases (such as low entanglement or low non-Clifford gate count) where one can independently learn efficient classical descriptions of each state using established techniques and share the description to compute the overlap. Instead, our results demonstrate that this is possible even in more complex scenarios where these "learn and share" methods are insufficient. Our proposal is scalable, as it just requires a number of two-copy Bell measurements and single-copy Pauli measurements that grows polynomially with both the number of qubits and the desired inverse-error, and can be implemented in the near term. Moreover, the required number of samples can be efficiently experimentally determined by the parties in advance, and our findings are robust against preparation errors. We anticipate that these results could have applications in quantum cryptography and verification.
title Highly-entangled, highly-doped states that are efficiently cross-device verifiable
topic Quantum Physics
url https://arxiv.org/abs/2501.11688