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arXiv · 2401.01671

Two-Unitary Complex Hadamard Matrices of Order $36$

Wojciech Bruzda·Karol Życzkowski
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Abstract

A family of two-unitary complex Hadamard matrices (CHM) stemming from a particular matrix, of size $36$ is constructed. Every matrix in this orbit remains unitary after operations of partial transpose and reshuffling which makes it a distinguished subset of CHM. It provides a novel solution to the quantum version of the Euler problem, in which each field of the Graeco-Latin square of size six contains a symmetric superposition of all $36$ officers with phases being multiples of sixth root of unity. This simplifies previously known solutions as all amplitudes of the superposition are equal and the set of phases consists of $6$ elements only. Multidimensional parameterization allows for more flexibility in a potential experimental realization.

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Wojciech Bruzda, Karol Życzkowski. 2024-01-03. Two-Unitary Complex Hadamard Matrices of Order $36$. https://doi.org/10.1515/spma-2024-0010

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