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arXiv · 1501.03684

Accuracy of the new pairing theory and its improvement

L. Y. Jia
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Abstract

Recently I proposed a new method for solving the pairing Hamiltonian with the pair-condensate wavefunction ansatz based on the Heisenberg equations of motion for the density matrix operators. In this work an improved version is given by deriving the relevant equations more carefully. I evaluate both versions in a large ensemble with random interactions, and the accuracy of the methods is given statistically in terms of root-mean-square derivations from the exact results. The widely used variational calculation is also done and the results and computing-time costs are compared.

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L. Y. Jia. 2015-01-15. Accuracy of the new pairing theory and its improvement. https://doi.org/10.1103/physrevc.88.064321

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