Multimode entanglement for fermions

Michel Rouleux

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arXiv · 1910.04790

Multimode entanglement for fermions

Michel Rouleux

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Abstract

We are motivated by tripartite entanglement for fermions. While GHZ or W states involve 3-fold intrication, we consider here piecewise intrication of 3 fermions in ${\bf C}^2$, namely of type $ab+bc+ca$. Before interaction with Stern-Gerlach apparatus, qu-bits are distinguishable; at the output however they turn into un-distinguishable particles, whose anti-symmetric wave function is of the form $\det(b-a,c-a)$ (affine determinant). More generally, $d+1$ intricated fermions in ${\bf C}^d$ can be represented by the anti-symmetric wave function $\det(a_1-a_0,a_2-a_0,\cdots,a_d-a_0)$. We investigate also properties of affine Slater determinants, as expectation values or reduced density matrices.

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Michel Rouleux. 2019-10-10. Multimode entanglement for fermions. https://arxiv.org/abs/1910.04790

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