Uncountably many inequivalent maximally entangled measurements for two qutrits

Every two-qubit measurement basis composed of maximally entangled eigenstates can be transformed into the Bell basis via local unitary operations.

For higher dimensions, in contrast, there exist inequivalent bases composed of maximally entangled eigenstates.

Here, we provide a single-parameter family of two-qutrit maximally entangled measurement bases, and demonstrate that none of the bases are equivalent to each other under local unitaries.

These bases are constructed from the continuous family of symmetric informationally complete sets of states in dimension three.

By studying the local unitary bases that generate the family of two-qutrit maximally entangled measurement bases, we construct the first examples of wild error bases in the smallest dimension where these can exist.

Finally, we discuss how distinct measurements in the family lead to differences in performance in several scenarios relevant in quantum information.