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arXiv · 1801.08677

Multiqubit UPB: The method of formally orthogonal matrices

Lin Chen·Dragomir Z. Djokovic
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Abstract

We use formal matrices whose entries we view as vector variables taking unit vectors values in one-qubit Hilbert spaces of a multiqubit quantum system. We construct many unextendible product bases (UPBs) of new sizes in such systems and provide a new construction of UPBs of $n$ qubits of cardinality $n+1$ when $n\equiv 3 \pmod{4}$. We also give a new method of constructing multiqubit entangled states with all partial transposes positive.

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Lin Chen, Dragomir Z. Djokovic. 2018-01-26. Multiqubit UPB: The method of formally orthogonal matrices. https://doi.org/10.1088/1751-8121/aac53b

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