Simultaneous determination of multiple low-lying energy levels on a superconducting quantum processor
Abstract
Determining the ground and low-lying excited states is critical in numerous scenarios. Recent work has proposed the ancilla-entangled variational quantum eigensolver (AEVQE) that utilizes entanglement between ancilla and physical qubits to simultaneously tagert multiple low-lying energy levels. In this work, we report the experimental implementation of the AEVQE on a superconducting quantum cloud platform, demonstrating the full procedure of solving the low-lying energy levels of the H molecule and the transverse-field Ising models (TFIMs). We obtain the potential energy curves of H and show an indication of the ferromagnetic to paramagnetic phase transition in the TFIMs from the average absolute magnetization. Moreover, we investigate multiple factors that affect the algorithmic performance and provide a comparison with ancilla-free VQE algorithms. Our work demonstrates the experimental feasibility of the AEVQE algorithm and offers a guidance for the VQE approach in solving realistic problems on publicly-accessible quantum platforms.
Keywords
Cite
@article{arxiv.2601.18514,
title = {Simultaneous determination of multiple low-lying energy levels on a superconducting quantum processor},
author = {Huili Zhang and Yibin Guo and Guanglei Xu and Yulong Feng and Jingning Zhang and Hai-feng Yu and S. P. Zhao},
journal= {arXiv preprint arXiv:2601.18514},
year = {2026}
}
Comments
arXiv admin note: substantial text overlap with arXiv:2507.14880. substantial text overlap with arXiv:2507.14880. substantial text overlap with arXiv:2507.14880. substantial text overlap with arXiv:2507.14880