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arXiv · 2402.12708

Quantum computation of conical intersections on a programmable superconducting quantum processor

Shoukuan Zhao·Diandong Tang·Xiaoxiao Xiao·Ruixia Wang·Qiming Sun·Zhen Chen·Xiaoxia Cai·Zhendong Li·Haifeng Yu·Wei-Hai Fang
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Abstract

Conical intersections (CIs) are pivotal in many photochemical processes. Traditional quantum chemistry methods, such as the state-average multi-configurational methods, face computational hurdles in solving the electronic Schr\"odinger equation within the active space on classical computers. While quantum computing offers a potential solution, its feasibility in studying CIs, particularly on real quantum hardware, remains largely unexplored. Here, we present the first successful realization of a hybrid quantum-classical state-average complete active space self-consistent field method based on the variational quantum eigensolver (VQE-SA-CASSCF) on a superconducting quantum processor. This approach is applied to investigate CIs in two prototypical systems - ethylene (C2H4) and triatomic hydrogen (H3). We illustrate that VQE-SA-CASSCF, coupled with ongoing hardware and algorithmic enhancements, can lead to a correct description of CIs on existing quantum devices. These results lay the groundwork for exploring the potential of quantum computing to study CIs in more complex systems in the future.

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Shoukuan Zhao, Diandong Tang, Xiaoxiao Xiao, Ruixia Wang, Qiming Sun, Zhen Chen, Xiaoxia Cai, Zhendong Li, Haifeng Yu, Wei-Hai Fang. 2024-02-20. Quantum computation of conical intersections on a programmable superconducting quantum processor. https://arxiv.org/abs/2402.12708

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