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On the Monomiality of Nice Error Bases

Andreas Klappenecker·Martin Roetteler
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Abstract

Unitary error bases generalize the Pauli matrices to higher dimensional systems. Two basic constructions of unitary error bases are known: An algebraic construction by Knill, which yields nice error bases, and a combinatorial construction by Werner, which yields shift-and-multiply bases. An open problem posed by Schlingemann and Werner (see http://www.imaph.tu-bs.de/qi/problems/6.html) relates these two constructions and asks whether each nice error basis is equivalent to a shift-and-multiply basis. We solve this problem and show that the answer is negative. However, we also show that it is always possible to find a fairly sparse representation of a nice error basis.

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Andreas Klappenecker, Martin Roetteler. 2003-01-16. On the Monomiality of Nice Error Bases. https://arxiv.org/abs/quant-ph/0301078

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