Many quantum algorithms are developed to evaluate eigenvalues for Hermitian matrices. However, few practical approach exists for the eigenanalysis of non-Hermintian ones, such as arising from modern power systems. The main difficulty lies in the fact that, as the eigenvector matrix of a general matrix can be non-unitary, solving a general eigenvalue problem is inherently incompatible with existing unitary-gate-based quantum methods. To fill this gap, this paper introduces a Variational Quantum Universal Eigensolver (VQUE), which is deployable on noisy intermediate scale quantum computers. Our new contributions include: (1) The first universal variational quantum algorithm capable of evaluating the eigenvalues of non-Hermitian matrices—Inspired by Schur’s triangularization theory, VQUE unitarizes the eigenvalue problem to a procedure of searching unitary transformation matrices via quantum devices; (2) A Quantum Process Snapshot technique is devised to make VQUE maintain the potential quantum advantage inherited from the original variational quantum eigensolver—With additional
This content will become publicly available on June 12, 2024
- Award ID(s):
- 1839136
- NSF-PAR ID:
- 10475599
- Publisher / Repository:
- Quantum Journal
- Date Published:
- Journal Name:
- Quantum
- Volume:
- 7
- ISSN:
- 2521-327X
- Page Range / eLocation ID:
- 1040
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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