Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Block-Circulant Complex Hadamard Matrices   A new method of obtaining a sequence of isolated complex Hadamard matrices
(CHM) of arbitrary order $N\geqslant 7$, based on block-circulant structures,
is presented. Several analytic and numerical examples resulted from the
modification of the Sinkhorn algorithm are discussed. In particular we present
new isolated matrices of order $9$ and $11$ which elements are not roots of
unity. We note novel connections between certain eight-dimensional matrices and
provide new insights towards classification of CHM for $N\geqslant 7$. These
contributions can find applications in Quantum Information Theory and
constructions of new families of Mutually Unbiased Bases or Unitary Error
Bases.

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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
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The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: physics
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The categories of this paper are: math-ph