Efficiency of neural quantum states in light of the quantum geometric tensor

Abstract Neural quantum state (NQS) ansätze have shown promise in variational Monte Carlo algorithms by their theoretical capability of representing any quantum state. However, the reason behind the practical improvement in their performance with an increase in the number of parameters is not fully...

Full description

Saved in:
Bibliographic Details
Main Authors: Sidhartha Dash, Luca Gravina, Filippo Vicentini, Michel Ferrero, Antoine Georges
Format: Article
Language:English
Published: Nature Portfolio 2025-03-01
Series:Communications Physics
Online Access:https://doi.org/10.1038/s42005-025-02005-4
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849761980403941376
author Sidhartha Dash
Luca Gravina
Filippo Vicentini
Michel Ferrero
Antoine Georges
author_facet Sidhartha Dash
Luca Gravina
Filippo Vicentini
Michel Ferrero
Antoine Georges
author_sort Sidhartha Dash
collection DOAJ
description Abstract Neural quantum state (NQS) ansätze have shown promise in variational Monte Carlo algorithms by their theoretical capability of representing any quantum state. However, the reason behind the practical improvement in their performance with an increase in the number of parameters is not fully understood. In this work, we systematically study the efficiency of a shallow neural network to represent the ground states in different phases of the spin-1 bilinear-biquadratic chain, as the number of parameters increases. We train our ansatz by a supervised learning procedure, minimizing the infidelity w.r.t. the exact ground state. We observe that the accuracy of our ansatz improves with the network width in most cases, and eventually saturates. We demonstrate that this can be explained by looking at the spectrum of the quantum geometric tensor (QGT), particularly its rank. By introducing an appropriate indicator, we establish that the QGT rank provides a useful diagnostic for the practical representation power of an NQS ansatz.
format Article
id doaj-art-67b1da3668b04f0ab832d662ca7a18cc
institution DOAJ
issn 2399-3650
language English
publishDate 2025-03-01
publisher Nature Portfolio
record_format Article
series Communications Physics
spelling doaj-art-67b1da3668b04f0ab832d662ca7a18cc2025-08-20T03:05:52ZengNature PortfolioCommunications Physics2399-36502025-03-01811910.1038/s42005-025-02005-4Efficiency of neural quantum states in light of the quantum geometric tensorSidhartha Dash0Luca Gravina1Filippo Vicentini2Michel Ferrero3Antoine Georges4Collège de France, Université PSLInstitute of Physics, École Polytechnique Fédérale de Lausanne (EPFL)Collège de France, Université PSLCollège de France, Université PSLCollège de France, Université PSLAbstract Neural quantum state (NQS) ansätze have shown promise in variational Monte Carlo algorithms by their theoretical capability of representing any quantum state. However, the reason behind the practical improvement in their performance with an increase in the number of parameters is not fully understood. In this work, we systematically study the efficiency of a shallow neural network to represent the ground states in different phases of the spin-1 bilinear-biquadratic chain, as the number of parameters increases. We train our ansatz by a supervised learning procedure, minimizing the infidelity w.r.t. the exact ground state. We observe that the accuracy of our ansatz improves with the network width in most cases, and eventually saturates. We demonstrate that this can be explained by looking at the spectrum of the quantum geometric tensor (QGT), particularly its rank. By introducing an appropriate indicator, we establish that the QGT rank provides a useful diagnostic for the practical representation power of an NQS ansatz.https://doi.org/10.1038/s42005-025-02005-4
spellingShingle Sidhartha Dash
Luca Gravina
Filippo Vicentini
Michel Ferrero
Antoine Georges
Efficiency of neural quantum states in light of the quantum geometric tensor
Communications Physics
title Efficiency of neural quantum states in light of the quantum geometric tensor
title_full Efficiency of neural quantum states in light of the quantum geometric tensor
title_fullStr Efficiency of neural quantum states in light of the quantum geometric tensor
title_full_unstemmed Efficiency of neural quantum states in light of the quantum geometric tensor
title_short Efficiency of neural quantum states in light of the quantum geometric tensor
title_sort efficiency of neural quantum states in light of the quantum geometric tensor
url https://doi.org/10.1038/s42005-025-02005-4
work_keys_str_mv AT sidharthadash efficiencyofneuralquantumstatesinlightofthequantumgeometrictensor
AT lucagravina efficiencyofneuralquantumstatesinlightofthequantumgeometrictensor
AT filippovicentini efficiencyofneuralquantumstatesinlightofthequantumgeometrictensor
AT michelferrero efficiencyofneuralquantumstatesinlightofthequantumgeometrictensor
AT antoinegeorges efficiencyofneuralquantumstatesinlightofthequantumgeometrictensor