论文标题
理查森·戈丁国家的过渡密度矩阵
Transition density matrices of Richardson-Gaudin states
论文作者
论文摘要
最近，降低的Bardeen-Cooper-Schrieffer Hamiltonian，Richardson-Gaudin（RG）州的基态特征向量已被用作波函数ANSATZ，以实现强相关性。该波函数在物理上代表具有恒定配对强度的一对电子（Geminals）。要超越均值场，必须在所有RG状态下发展波功能。这需要用于过渡密度矩阵的实际表达方式，也需要一种在扩展中最重要的状态。在此贡献中，我们介绍了过渡密度矩阵元素的表达式，并为半填充的纠察模型进行数值计算。 RG国家没有Slater-Condon规则，尽管Aufbau原则的类似物被证明在选择哪些州很重要。
Recently, ground state eigenvectors of the reduced Bardeen-Cooper-Schrieffer Hamiltonian, Richardson-Gaudin (RG) states, have been employed as a wavefunction ansatz for strong correlation. This wavefunction physically represents a mean-field of pairs of electrons (geminals) with a constant pairing strength. To move beyond the mean-field, one must develop the wavefunction in the basis of all the RG states. This requires both practical expressions for transition density matrices and an idea of which states are most important in the expansion. In this contribution, we present expressions for the transition density matrix elements and calculate them numerically for half-filled picket fence models. There are no Slater-Condon rules for RG states, though an analogue of the aufbau principle proves to be useful in choosing which states are important.
