Bauman Nicholas P, Liu Hongbin, Bylaska Eric J, Krishnamoorthy Sriram, Low Guang Hao, Granade Christopher E, Wiebe Nathan, Baker Nathan A, Peng Bo, Roetteler Martin, Troyer Matthias, Kowalski Karol
Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
Microsoft Quantum, Redmond, Washington 98052, United States.
J Chem Theory Comput. 2021 Jan 12;17(1):201-210. doi: 10.1021/acs.jctc.0c00909. Epub 2020 Dec 17.
This paper explores the utility of the quantum phase estimation (QPE) algorithm in calculating high-energy excited states characterized by the promotion of electrons occupying core-level shells. These states have been intensively studied over the last few decades, especially in supporting the experimental effort at light sources. Results obtained with QPE are compared with various high-accuracy many-body techniques developed to describe core-level states. The feasibility of the quantum phase estimator in identifying classes of challenging shake-up states characterized by the presence of higher-order excitation effects is discussed. We also demonstrate the utility of the QPE algorithm in targeting excitations from specific centers in a molecule. Lastly, we discuss how the lowest-order Trotter formula can be applied to reducing the complexity of the ansatz without affecting the error.
本文探讨了量子相位估计（QPE）算法在计算以占据核心能级壳层的电子跃迁为特征的高能激发态方面的效用。在过去几十年中，这些态受到了广泛研究，特别是在支持光源实验方面。将QPE获得的结果与为描述核心能级态而开发的各种高精度多体技术进行了比较。讨论了量子相位估计器识别以高阶激发效应为特征的具有挑战性的振激态类别的可行性。我们还展示了QPE算法在针对分子中特定中心的激发方面的效用。最后，我们讨论了如何应用最低阶 Trotter 公式来降低 ansatz 的复杂度而不影响误差。
