发表机构
Graduate School of System Informatics, Kobe University（神户大学系统信息研究学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出用两体累积量近似将投影式关联变换中的三体有效算符降为至多二体算符，在HEAT集合和CAS-pTC模型上验证，显著减少量子比特泡利字符串数量。
AI 中文摘要
投影式关联变换通过相似变换与双子函数$f(r_{12})$恢复短程电子关联，代价是有效哈密顿量包含三体项。我们利用三粒子约化密度矩阵的两体累积量（2C）近似，将该三体项替换为秩至多为二的有效算符。2C三体能量以无累积量形式写出，有效单体和两体相互作用则作为其对约化密度矩阵的偏导数导出。该截断在HEAT集合的原子化和反应能量上以CCSD(T)方法评估，并在CAS-pTC模型上测试，其下折叠哈密顿量保持在量子比特寄存器上，泡利字符串数量从轨道数的六次幂降至四次幂。
英文摘要
Projective transcorrelation recovers the short-range electron correlation by a similarity transformation with a geminal function $f(r_{12})$, at the cost of an effective Hamiltonian containing a 3-body term. We replace the term by an effective operator of rank at most two, obtained from the two-body cumulant (2C) approximation to the three-particle reduced density matrix. The 2C 3-body energy is written without cumulants, and the effective one- and two-body interactions are derived as its partial derivatives with respect to the reduced density matrices. The truncation is assessed on the atomization and reaction energies of the HEAT set with CCSD(T), and on the CAS-pTC model, whose downfolded Hamiltonian is held on a qubit register with the number of Pauli strings reduced from the sixth power of the orbital count to the fourth.
CommentsCC option is corrected
