Qubit coupled cluster singles and doubles variational quantum eigensolver ansatz for electronic structure calculations
Qubit coupled cluster singles and doubles variational quantum eigensolver ansatz for electronic structure calculations
复制标题
DOI：
10.1088/2058-9565/abbc74
复制
发表时间：
2020-10
影响因子：
6.7
通讯作者：
Rongxin Xia;S. Kais
中科院分区：
文献类型：
--
作者：
Rongxin Xia;S. Kais
变分量子本征解器（VQE）是近期量子计算的一个重要应用。在众多的VQE算法中，酉耦合簇单双激励（UCCSD）VQE算法具有较高的精度，受到了广泛的研究兴趣。然而，基于费米激发的UCCSD VQE在使用Jordan Wigner变换时需要额外的宇称项。在这里，我们介绍了一种新的VQE的基于粒子保持交换门实现量子比特的激发。所提出的VQE anomaly的门复杂度上限为O（n 4）的所有到所有的连接，其中n是量子比特的数量的哈密顿量。简单分子系统如BeH2，H2O，N2，H4和H6的数值结果使用所提出的VQE方法给出了非常精确的结果，误差约为10−3 Hartree。
Variational quantum eigensolver (VQE) for electronic structure calculations is believed to be one major potential application of near term quantum computing. Among all proposed VQE algorithms, the unitary coupled cluster singles and doubles excitations (UCCSD) VQE ansatz has achieved high accuracy and received a lot of research interest. However, the UCCSD VQE based on fermionic excitations needs extra terms for the parity when using Jordan–Wigner transformation. Here we introduce a new VQE ansatz based on the particle preserving exchange gate to achieve qubit excitations. The proposed VQE ansatz has gate complexity up-bounded to O(n 4) for all-to-all connectivity where n is the number of qubits of the Hamiltonian. Numerical results of simple molecular systems such as BeH2, H2O, N2, H4 and H6 using the proposed VQE ansatz gives very accurate results within errors about 10−3 Hartree.