Mutually Unbiased Unitary Bases of Operators on -dimensional Hilbert Space
arXiv:2003.12201 · doi:10.1142/S0219749919410260
Abstract
Analogous to the notion of mutually unbiased bases for Hilbert spaces, we consider mutually unbiased unitary bases (MUUB) for the space of operators, , acting on such Hilbert spaces. The notion of MUUB reflects the equiprobable guesses of unitary in one bases of when estimating a unitary operator in another. Though, for prime dimension , the maximal number of MUUBs is known to be , there is no known recipe for constructing them, assuming they exist. However, one can always construct a minimum of three MUUBs, and the maximal number is approached for very large values of . MUUBs can also exists for some -dimensional subspace of with the maximal number being .
11 pages, 1 figure