Elementary formula for entanglement entropies of fermionic systems
Péter Lévay, Szilvia Nagy, Jānos Pipek · Physical Review A · 2005
An elementary formula for the von Neumann and R\'enyi entropies describing quantum correlations in two-fermionic systems having four single-particle states is presented. An interesting geometric structure of fermionic entanglement is revealed. A connection with the generalized Pauli principle is established.