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arXiv · 2402.11785

The construction of multiqubit unextendible product bases

Caohan Cheng·Lin Chen
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Abstract

The unextendible orthogonal matrices (UPBs) can be used for various problems in quantum information. We provide an algorithm to check if two UPBs are non-equivalent to each other. We give a method to construct UPBs and we apply this method to find all $5$-qubit UPBs of size eight. We apply the algorithm to check if the $5$-qubit UPBs of size eight are non-equivalent to each other. Based on all the $5$-qubit UPBs of size eight, we propose a theorem for constructing a new UPB non-equivalent to a given one.

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Caohan Cheng, Lin Chen. 2024-02-19. The construction of multiqubit unextendible product bases. https://arxiv.org/abs/2402.11785

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