Exact two-body expansion of the many-particle wave function
Exact two-body expansion of the many-particle wave function
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DOI：
10.1103/physreva.102.030802
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发表时间：
2020-09-21
影响因子：
2.9
通讯作者：
Mazziotti, David A.
中科院分区：
文献类型：
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作者：
Mazziotti, David A.
解决强相关电子问题的进展受到波函数的指数复杂性的阻碍。先前的工作为基态波函数建立了精确的两体指数积展开。通过发展Dalgarno-Lewis微扰理论的简化密度矩阵模拟，我们证明了(i)两体指数积展开是快速和全局收敛的，每个算子表示一个重整化微扰理论的阶，（ii）展开的能量在解附近二次收敛，（iii）展开对基态和激发态都是精确的。二体展开提供了多粒子波函数的简化参数化以及两粒子简化密度矩阵，在传统计算机和量子计算机上都有潜在的应用，用于强相关量子系统的研究。我们用分子链H-4和H-5的收缩薛定谔方程的精确解证明了这一结果。
Progress toward the solution of the strongly correlated electron problem has been stymied by the exponential complexity of the wave function. Previous work established an exact two-body exponential product expansion for the ground-state wave function. By developing a reduced density-matrix analog of Dalgarno-Lewis perturbation theory, we prove here that (i) the two-body exponential product expansion is rapidly and globally convergent with each operator representing an order of a renormalized perturbation theory, (ii) the energy of the expansion converges quadratically near the solution, and (iii) the expansion is exact for both ground and excited states. The two-body expansion offers a reduced parametrization of the many-particle wave function as well as the two-particle reduced density matrix with potential applications on both conventional and quantum computers for the study of strongly correlated quantum systems. We demonstrate the result with the exact solution of the contracted Schrodinger equation for the molecular chains H-4 and H-5.