Generation and discrimination of a type of four-partite entangled state

Abstract

Recently, a genuine four-qubit entangled state ${\ensuremath{\mid}{\ensuremath{\chi}}^{00}⟩}_{3214}$ has been proposed [Y. Yeo and W. K. Chua, Phys. Rev. Lett. 96, 060502 (2006)]. This state has many interesting entanglement properties and possible applications in quantum information processing and fundamental tests of quantum physics. Here we present a simple scheme for generating such a state in an ion-trap system. We also demonstrate how to discriminate between the 16 basis states ${{\ensuremath{\mid}{\ensuremath{\chi}}^{ij}⟩}_{3214}={\ensuremath{\sigma}}_{3}^{i}{\ensuremath{\sigma}}_{1}^{j}{\ensuremath{\mid}{\ensuremath{\chi}}^{00}⟩}_{3214},i,j=0,1,2,3}$.