Entanglement witnesses from mutually unbiased bases
Dariusz Chruściński, Gniewomir Sarbicki, Filip Wudarski · Physical Review A · 2018
We provide a class of entanglement witnesses constructed in terms of mutually unbiased bases (MUBs). This construction reproduces many well-known examples such as the celebrated reduction map and the Choi map together with its generalizations. We illustrate our construction by a detailed analysis of the three-dimensional case: In this case, one obtains a family of entanglement witnesses parametrized by an $L$-dimensional torus ($L=2,3,4$ being a number of MUBs used in the construction).