English

$BCCB$ complex Hadamard matrices of order 9, and MUBs

Quantum Physics 2016-04-21 v1

Abstract

A new type of complex Hadamard matrices of order 9 are constructed. The studied matrices are symmetric, block circulant with circulant blocks (BCCBBCCB) and form an until now unknown non-reducible and non-affine two-parameter orbit. Several suborbits are identified, including a one-parameter intersection with the Fourier orbit F9(4)F_{9}^{(4)}. The defect of this new type of Hadamard matrices is observed to vary, from a generic value 2 to the anomalous values 4 and 10 for some sub-orbits, and to 12 and 16 for some single matrices. The latter matrices are shown to be related to complete sets of MUBs in dimension 9.

Keywords

Cite

@article{arxiv.1604.03770,
  title  = {$BCCB$ complex Hadamard matrices of order 9, and MUBs},
  author = {Bengt R. Karlsson},
  journal= {arXiv preprint arXiv:1604.03770},
  year   = {2016}
}

Comments

14 pages, 3 figures