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arXiv · 1404.5287

Quantification of entanglement entropy in helium by the Schmidt-Slater decomposition method

Chien-Hao Lin·Yew Kam Ho
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Abstract

In this work, we present an investigation on the spatial entanglement entropies in the helium atom by using highly correlated Hylleraas functions to represent the S-wave states. Singlet-spin 1sns 1Se states (with n = 1 to 6) and triplet-spin 1sns 3Se states (with n = 2 to 6) are investigated. As a measure on the spatial entanglement, von Neumann entropy and linear entropy are calculated. Furthermore, we apply the Schmidt-Slater decomposition method on the two-electron wave functions, and obtain eigenvalues of the one-particle reduced density matrix, from which the linear entropy and von Neumann entropy can be determined.

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Chien-Hao Lin, Yew Kam Ho. 2014-04-21. Quantification of entanglement entropy in helium by the Schmidt-Slater decomposition method. https://doi.org/10.1007/s00601-014-0900-9

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