Spatial entanglement in two-electron atomic systems

Abstract

Recently, there has been considerable interest in investigating quantum entanglement in two-electron systems, such as two-electron model atoms and quantum dots. In this work, the quantum entanglement of the helium atom and helium-like ions are explored using the two-electron wave functions constructed by the B-spline basis. As a measure of the spatial entanglement, the linear entropy of the reduced density matrix is investigated for the ground state and the singlet excited 1sns 1 S states, with n = 2-10, of the helium atom. The variation of the spatial entanglement with the nuclear charges Z = 2-15 for the helium-like ions is reported. Results are compared with the existing predictions.

Doubly Excited Resonance States of Helium Atom: Complex Entropies

“…In particular, there has been a remarkable increase of interest in exploring properties of various quantum composite systems [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. In recent years, both the entanglement and Shannon Entropy in helium and helium-like ions have also accelerated a great research attention [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. However, studies on the correlation in resonance states have not yet drawn much attention.…”

The von Neumann entanglement entropy for Wigner-crystal states in one dimensional N-particle systems

“…For example, some light has been shed on entanglement both in quantum dot systems [6][7][8][9][10][11][12][13][14][15] and in systems of harmonically interacting particles in a harmonic trap (the so-called Moshinsky atom) [16][17][18][19][20][21][22][23]. Special attention has also been paid to the study of entanglement in the helium atoms and helium ions [24][25][26][27][28][29][30][31][32]. The effect of the confinement on the entanglement in the ground state of the helium atom has also been discussed in the literature [33].…”

Ground-State Entanglement Properties of Helium Atom in a Finite Spherical Cavity

“…In particular, it provides an alternative tool to quantify the quantum correlation between the indistinguishable constituent particles. Being the best candidate to study the behavior of quantum correlation between the fermions, the helium-like atoms have been in recent years intensively studied in contexts of their entanglement properties [14][15][16][17][18][19][20][21]. However, studies on entanglement properties of confined helium-like atoms are still limited.…”