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arXiv · 2510.13544

State-Specific Orbital Optimization for Enhanced Excited-States Calculation on Quantum Computers

Guorui Zhu·Joel Bierman·Jianfeng Lu·Yingzhou Li
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Abstract

We propose a state-specific orbital optimization scheme for improving the accuracy of excited states of the electronic structure Hamiltonian for the use on near-term quantum computers, which can be combined with any overlap-based excited-state quantum eigensolver. We derived the gradient of the overlap term between different states generated by different orbitals with respect to the orbital rotation matrix and use the gradient-based optimization methods to optimize the orbitals. This scheme allows for more flexibility in the choice of orbitals. We implement the state-specific orbital optimization scheme with the variational quantum deflation (VQD) algorithm, and show that it achieves higher accuracy than the state-averaged orbital optimization scheme on various molecules including H4 and LiH.

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Guorui Zhu, Joel Bierman, Jianfeng Lu, Yingzhou Li. 2025-10-15. State-Specific Orbital Optimization for Enhanced Excited-States Calculation on Quantum Computers. https://arxiv.org/abs/2510.13544

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