2018/10/21 by Lin Chen, Kai Wang, Chen, Lin +7
Computer Science · Physics and Astronomy · #Quantum Information and Cryptography #Quantum Computing Algorithms and Architecture #Quantum Mechanics and Applications
paper · pdf · doi:10.48550/arxiv.1810.08932
The 4-qubit unextendible product basis (UPB) has been recently studied by [Johnston, J. Phys. A: Math. Theor. 47 (2014) 424034]. From this result we show that there is only one UPB of size 6 and six UPBs of size 9 in \cH=\bbC2\ox\bbC2\ox\bbC4, three UPBs of size 9 in \cK=\bbC4\ox\bbC4, and no UPB of size 7 in \cH and \cK. Furthermore we construct a 4-qubit positive-partial-transpose (PPT) entangled state \r of rank seven, and show that it is also a PPT entangled state in \cH and \cK, respectively. We analytically derive the geometric measure of entanglement of a special \r.