Towards Heisenberg Scaling: Measurement-Efficient Non-Orthogonal Quantum Eigensolver

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ren, Hang, Zhang, Yipei, Scharnhorst, Thilo, Whaley, K. Birgitta
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910279375257600
author Ren, Hang
Zhang, Yipei
Scharnhorst, Thilo
Whaley, K. Birgitta
author_facet Ren, Hang
Zhang, Yipei
Scharnhorst, Thilo
Whaley, K. Birgitta
contents The Non-Orthogonal Quantum Eigensolver (NOQE) provides an accurate framework for electronic-structure calculations, but the estimation of its Hamiltonian and overlap matrix elements relies on sampling and requires $O(1/\varepsilon^2)$ circuit repetitions to achieve additive precision $\varepsilon$. Here, we reformulate this matrix-element estimation step as a collection of amplitude-estimation tasks and integrate iterative quantum amplitude estimation into the NOQE workflow. The resulting protocol achieves near-Heisenberg query complexity $O(1/\varepsilon)$ for these estimation tasks, by replacing incoherent statistical averaging with coherent amplitude amplification. We present explicit circuit constructions and the corresponding implementation procedure. Numerical simulations for the electronic states of the hydrogen molecule show that the proposed method reaches chemical accuracy with substantially fewer total queries than the original sampling-based protocol. Overall, this work provides a measurement-efficient route to high-precision energy estimation and illustrates how sampling-limited quantum algorithms can be systematically reformulated to leverage quantum coherence and achieve lower measurement costs.
format Preprint
id arxiv_https___arxiv_org_abs_2606_01589
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Towards Heisenberg Scaling: Measurement-Efficient Non-Orthogonal Quantum Eigensolver
Ren, Hang
Zhang, Yipei
Scharnhorst, Thilo
Whaley, K. Birgitta
Quantum Physics
The Non-Orthogonal Quantum Eigensolver (NOQE) provides an accurate framework for electronic-structure calculations, but the estimation of its Hamiltonian and overlap matrix elements relies on sampling and requires $O(1/\varepsilon^2)$ circuit repetitions to achieve additive precision $\varepsilon$. Here, we reformulate this matrix-element estimation step as a collection of amplitude-estimation tasks and integrate iterative quantum amplitude estimation into the NOQE workflow. The resulting protocol achieves near-Heisenberg query complexity $O(1/\varepsilon)$ for these estimation tasks, by replacing incoherent statistical averaging with coherent amplitude amplification. We present explicit circuit constructions and the corresponding implementation procedure. Numerical simulations for the electronic states of the hydrogen molecule show that the proposed method reaches chemical accuracy with substantially fewer total queries than the original sampling-based protocol. Overall, this work provides a measurement-efficient route to high-precision energy estimation and illustrates how sampling-limited quantum algorithms can be systematically reformulated to leverage quantum coherence and achieve lower measurement costs.
title Towards Heisenberg Scaling: Measurement-Efficient Non-Orthogonal Quantum Eigensolver
topic Quantum Physics
url https://arxiv.org/abs/2606.01589