Two Definitions of the Gell-Mann Channels-A Comparative Analysis

In the present paper, we compare two unequivalent definitions of the Gell-Mann channels. It turns out that both definitions coincide for qubits and for qutrits one is more restrictive than the other. In higher dimensions, there exist some constraints under which both channels describe the same dynamics. Finally, we find the time-local generators for a class of the Gell-Mann channels. We relate our results to the algebra of SU(n) generators.